Etymology: Partly (i) cognate with or formed similarly to Old Frisian in- (West Frisian yn- ), Old Dutch in- (Middle Dutch in- , Dutch in- ), Old Saxon in- (Middle Low German in- ), Old High German in- , īn- (Middle High German in- , īn- , German in- , ein- ), Old Icelandic í- , inn- , Old Swedish in- (Swedish in- ), Old Danish in- (Danish ind- ), Gothic in- , inn- < the same Germanic base as in prep. (also, in the individual languages, in stressed position, especially as a separable particle, < the reflexes of the ultimately related Germanic base of in adv.), and partly (ii) directly < in adv. and in prep.For the blurring of the distinction between this prefix and in- prefix³ in later use, see discussion at the latter entry. With the form en- compare en- prefix¹, and see discussion of prefix substitution at that entry. Nominal and adjectival compounds. In Old English, in- occurs in stressed position (sometimes written inn- ) prefixed to nouns, adjectives, and their derivatives: (1) with ordinary nouns (and occasionally adjectives) in the sense ‘that is within’, ‘internal’ (compare sense 1a(a)), e.g. inādl internal disease (compare adle n.), inbyrde (adjective) born on the estate (compare birde n.), incniht household servant (compare knight n.), incofa inner chamber (compare cove n.¹), ingehygd mind, conscience, understanding, knowledge, intention (compare hight n.¹), inland demesne land (see inland n.), inorf household goods, furniture (compare orf n.¹), inwærc internal pain (compare wark n.¹), etc.; (2) with verbal nouns and nouns of action and agent nouns derived from verbal roots, expressing inward motion or direction (compare sense 1a(b)), e.g. incyme coming in, entrance (see income n.¹), infær entrance, entry, access (see infare n.), ingang entrance, entry (see ingang n.), ingenga intruder, inlād import tax, admission fee, literally ‘carriage in’, etc.; (3) with elements forming adjectives, either related to the nouns in (1), e.g. inlende native, indigenous, or derived from verbs (participial adjectives), e.g. inboren native, indigenous (see inborn adj.), infangen , literally ‘caught within’ (only in infangenþēof infangthief n.). Several of the above formations (e.g. incniht , ingehygd , inlende ) have cognates or parallels in other Germanic languages. New formations of the same kind continue to be found in Middle English and later English, e.g. incomer n., inseer n., in-timber n., inturn n., inwit n., etc. Verbal compounds: (i) with unstressed prefix. In Anglian Old English, in- occurs as an unstressed verbal prefix (the expected pattern) in a small number of verbs showing the reflex of an original Germanic prefix from the same base as in prep., e.g. inbærnan to set on fire (see burn v.¹), inlīhtan enlight v., etc., which in West Saxon show characteristic replacement of in- by on- , e.g. onbærnan , onlīehtan onlight v.¹, etc. (compare discussion at on- prefix). Consequently, it is also occasionally found by false substitution in verbs which have on- as the genuine reflex of the Germanic base of on- prefix, e.g. inǣlan for onǣlan anneal v., inblāwan for onblāwan anblow v., (Northumbrian) infinda for onfindan (see afind v.), although the latter could alternatively show the influence of Latin invenīre (compare discussion below). Probably also by the same process of false substitution (although compare Old High German in- , variant of int- and- prefix) the (unstressed) Anglian Old English verbal prefix in- sometimes represents the reflex of the unstressed form of the Germanic base of and- prefix (whose usual form in Old English is on- : see β. forms at that entry), as e.g. inbyrgan to taste (compare onbyrgan ), inhrēran to move, stir (compare onhrēran ; see rore v.), and (expressing reversal; compare un- prefix²) inbindan to unbind (compare onbindan unbind v.), inwrēon to uncover, reveal (compare onwrēon unwry v.). The identity of the prefix involved is not always easy to determine, compare e.g. Anglian inginnan to begin, which could conceivably represent an underlying formation in either in- prefix¹, on- prefix, or and- prefix (compare discussion at ongin v.). Very few of these verbs survived into Middle English (inlighte is perhaps the sole exception: see α. forms at enlight v.). Verbal compounds: (ii) with stressed prefix. In addition, in also occurs in Old English with verbs (and their derivatives), in stressed position, as a separable particle (formed on in adv.), its position dependent on the form of the verb and grammar of the sentence, typically following the verb in the imperative and in the present and past indicative in the principal sentence, but in the subordinate clause and in all other moods or parts of the verb including the infinitive and participles (and all nominal derivatives) standing immediately before the verb (compare discussion at out- prefix). In the latter position the word can be interpreted as showing either in adv. or in- prefix¹. Typically with verbs of motion or change of state, e.g. inbringan inbring v., incuman income v., infaran infare v., infēran (see fere v.¹), ingangan (see gang v.¹), ingān ingo v., inlǣdan inlead v., all of which have cognates or parallels in other Germanic languages. Compare sense 1c. The regular position of in before the verb in the infinitive and participles naturally tended to make the collocation pass into a compound, especially in the case of nominal and adjectival derivatives. (In these latter forms in- remained fixed despite the regular repositioning of the particle in later English after the infinitive and other verbal forms, which is why such forms as incoming , income (noun), incomer , indwelling , indweller , ingrowing , ingrown , inset (adjective), intake (noun), etc. correspond to come in , dwell in , grow in , set in , take in , etc.) In Middle English the rules of word order changed. On the one hand the particle began to be placed after or away from the verb in the subordinate clause, the infinitive, etc.; on the other hand the older usage of the particle preceding the infinitive was often extended to the indicative in the principal clause. This was partly the result of a general levelling and loss of old syntactic distinctions; however, these novelties in word order were especially employed by metrical writers, as facilitating the exigencies of rhythm and rhyme, and it is chiefly in verse that they are found. (Word division in Old English and Middle English examples frequently reflects editorial choices of modern editors of texts, rather than the practice of the manuscripts.) Latin models. The Old English verbs of motion or change of state noted above also occur frequently in translations from Latin (rendering Latin verbs in in- in- prefix³ or occasionally intro- intro- prefix, sometimes in element-by-element glosses). Numerous other formations modelled on Latin verbs are attested, e.g. (in Old English) ineardian (rendering Latin inhabitare : see erde v.), infeallan (rendering Latin incidere : see fall v.), ingēotan (rendering Latin infundere : see inyet v.), innīwian (rendering Latin innovare : see innew v.), inrǣsan (rendering Latin irruere and irrumpere : see rese v.²), insettan to institute (rendering Latin instituere : see inset v.), and (in Middle English, especially in the Wycliffite Bible) inclepe v. (rendering Latin invocare ), incrook v. (rendering Latin incurvare ), indelve v. (rendering Latin infodere ), inlap v. (rendering Latin involvere and implicare ), inlow v. (rendering Latin inflammare ), insmite v. (rendering Latin incutere ), etc. Also in nominal formations after Latin models, e.g. (in Old English) innīwung (rendering Latin innovatio ), inrēcels (rendering Latin incensum ; compare rechels n.), inwrīting (rendering Latin inscriptio : see inwriting n.), and (in Middle English) inrace n. (rendering Latin incursus ), infollowing n. (rendering Latin insectatio ), inrunning n. (rendering Latin incursus ), etc. Very few of these formations survived into modern English. Other formations. Old English inlagian inlaw v. and early Middle English inlaȝe inlaw n.¹ show formations on in prep. For modern adjectival formations derived from prepositional phrases with in prep. see note at sense 2.

Etymology: Cognate with Middle Dutch in- (Dutch in- ), Middle Low German in- , Middle High German in- (German in- , now chiefly regional), Old Icelandic í- , Norwegian (Bokmål and Nynorsk) inn- , (Nynorsk) i- , Danish †ind- < the same Germanic base as in- prefix¹.The semantic development was probably from ‘inly, intimately’ to ‘thoroughly’, and hence ‘exceedingly, very’; see further A. Hœfer ‘Das intensive in’ in Germania 15 (1870) 61–5. In North Germanic the prefix is also used with moderating force, in sense ‘approaching the quality of, somewhat’ (compare e.g. Icelandic ígrænn ‘greenish’, beside Old Icelandic (poetic) ígrœnn ‘very green, evergreen’; Norwegian (Nynorsk) iraud ‘reddish’, beside Norwegian regional iraud ‘very red’); with similar semantic range compare e.g. pretty adv., quite adv. Old English formations include indryhten noble, excellent (compare drightin n.), indryhtu glory, honour, inflēde (of a river) full of water (compare flede v.), infrōd very wise (compare frede v.), inhold very loyal (compare hold adj.). Middle English formations include ingoodly very beautiful (15th cent.), inheavy very depressed (15th cent.), inred adj. (13th cent.), inrichly (adverb) very richly (15th cent.), inthoroughly (adverb) very thoroughly (15th cent.), inwise adj. (15th cent.); frequent in the works of Charles d'Orleans.

Etymology: < classical Latin in-, prefix < in , adverb and preposition (see in prep.); used in combination with verbs or their derivatives, less commonly with other parts of speech, with the senses ‘into, in, within, on, upon, towards, against’, sometimes expressing onward motion, sometimes intensive, and in other cases with no obvious modification of the meaning of the prefixed word. Form history. In earlier Latin, in- was generally retained unchanged before all consonants; but in later times it was assimilated to the following consonant, becoming il- before l , im- before a labial, ir- before r , while it was lost altogether before -gn- . These changes are retained in English, as in e.g. illate v., imbue v., immit v., impel v., irradiate v., ignore v.: see il- prefix¹, im- prefix¹, ir- prefix¹ In Old French, in inherited words, in- , im- , became en- , em- ; but learned words derived or formed from Latin, especially in later times, regularly retained in- , im- . In English there was a growing tendency, from the 14th century onward, in words in which the Latin derivation was evident, to substitute in- , im- for en- , em- (compare e.g. increase v., inherit v., indebted adj.). This was even extended to some words which were not obviously, or not at all, of Latin origin, including some of those in which en- , em- was prefixed to words of Old English or other origin. (See en- prefix¹.) Conversely, some words borrowed directly from Latin nonetheless show (French) en- , em- in English. Hence, a large number of words occur in the 15th and 16th centuries with both forms of the prefix, and some have retained both forms to the present day, either with no distinction of sense, as in enclose v., inquire v., or with differentiation, as ensure v., insure v. The general tendency (though with numerous exceptions) has been to prefer in- , im- in words evidently derived from Latin, reserving en- , em- , for words formed in French and not having a Latin type, or in which the Latin type is obscured by phonetic change, and for words formed in English on the analogy of these. In this Dictionary, words are placed under their usual (current) form, whether in- (im- ) or en- (em- ). Ambiguity or merger with native prefix. Since this prefix and in- prefix¹ are identical in form, and to a great extent in sense, they came in later use to be felt as one and the same prefix, and hence in many cases it can be impossible to determine whether an English word has been formed with in- prefix¹ or in- prefix³ (for an early instance of a type from which ambiguity could readily have arisen compare inlead v., formed within English from in- prefix¹ but on the model of a Latin word in in- in- prefix³).

Etymology: < classical Latin in-, prefixed to adjectives and their derivatives, rarely to other words, to express negation or privation, as in e.g. infēlix unhappy ( < fēlix happy), inutilis useless ( < utilis useful), innocēns unhurtful, innocent ( < nocēns hurtful), indoctus unlearned ( < doctus learned) < the same Indo-European base as un- prefix¹ (hence also cognate with ancient Greek αν- an- prefix²). Form history. In earlier Latin, in- was used before all consonants, but in later times was subject to the same assimilations as in- prefix³, as in illitterātus illiterate adj., immensus immense adj., irregulāris irregular adj., and was reduced to i- before gn , as in ignārus ignorant, ignōscere to overlook, forgive. In a few Old French words, Latin in- became en- (as seen also with in- prefix³), e.g. Latin inimīcus , Old French enemi enemy n.¹, Latin invidia , Old French envie envy n.; but most French words containing this prefix are of learned formation, and retain Latin in- (il- , im- , ir- ), as is the case also in English with words derived either through French, or directly from Latin. History of use in English. Found frequently in borrowings from Latin, either directly or via French, from at least the 13th century, as e.g. inobedience n., incest n., innocent adj. New formations within English are found from at least the 14th century, as e.g. innoyandness n., indepartable adj., ineschewable adj., indisposed adj. Generally prefixed to words ultimately of Latin or Romance origin, although exceptions are found from as early as the 16th century, e.g. inspeakable adj., intellable adj., infree adj. (probably in many cases resulting from remodelling of earlier formations in un- prefix¹). On variation between words showing in- and (native) un- prefix¹ (as e.g. incautious adj., uncautious adj.), see discussion at that entry.