Etymology: < classical Latin costum (also costos, costus) an aromatic plant (probably the thistle costus) or its powdered root, in post-classical Latin probably also in sense ‘costmary’ (although this is only securely attested at a late date (15th cent. in a British source); in earlier post-classical Latin texts the precise sense is often difficult to distinguish) < Hellenistic Greek κόστος (also κόστον ), denoting an aromatic root used as spice < Sanskrit kuṣṭha the thick aromatic root of the thistle costus, native to Kashmir, which was imported as a spice by the Greeks and Romans. Compare Arabic kust , kusṭ , (now usually) qusṭ (also < Sanskrit kuṣṭha ; perhaps via Syriac quštā ). With sense 2 compare later costus n.Compare Old French, French †coste (c1150; French (now regional) coq , with folk-etymological alteration after coq cock n.¹), Old French, Middle French cost (12th cent.), both in senses ‘costmary’ and ‘plant whose root is used as spice, probably the thistle costus’ (it is often difficult to determine in early use which sense is intended); also Old Occitan cost (13th cent.), Italian costo (1310), both in sense ‘costmary’, and further Old Saxon kost, Old High German kost (strong masculine), kosto (weak masculine), apparently in sense ‘costmary’, and also Middle Dutch coste wild marjoram (15th cent.; Dutch †kost, †koste).

Etymology: Probably < early Scandinavian (compare Old Icelandic kostr choice, terms, chance, opportunity, state, condition, good quality, Old Swedish koster choice, state, condition (Swedish †kost ), Old Danish kostær condition, possession, thing (Danish koster (plural) possessions, goods, things)), cognate with Old High German kost judgement, council, decision, Gothic kustus proof, trial < the same Indo-European base as classical Latin gustus taste (compare gust n.²), showing an extended form of an ablaut variant (zero-grade) of the Germanic base of choose v.; related forms are shown by ancient Greek γεύεσθαι to taste and the Germanic base of cust n.¹ Compare also costen v.¹In Old English a strong masculine; the likely Scandinavian etymon shows the reflex of a u -stem noun derived from the same Germanic base as the inherited Old English strong feminine (i -stem) cyst cust n.¹ (although some of the Scandinavian forms could alternatively be explained as being more directly equivalent to cyst ). Old English cost is not attested before the later 10th cent., chiefly in sources showing Scandinavian influence or associations, and its use clearly overlaps with the semantic development of the Scandinavian derivatives of the Germanic base. It is therefore usually assumed to be a loanword; for further discussion see S. M. Pons-Sanz Lexical Effects Anglo-Scand. Ling. Contact on Old Eng. (2013) 108–9, 229–30. With Old English ǣngum coste by any means, in any way (see quot. OE at sense 1), compare uses such as Old Icelandic engum kosti by no means, nǫkkurs kostar in any way. With Old English þæs costes þe on condition that (see sense 2) compare Old Icelandic at þeim kosti on that condition. In Middle English occasionally difficult to distinguish from cost n.³ 2 in some contexts, especially in phrases.

Etymology: < Anglo-Norman and Old French coste, couste (feminine), Anglo-Norman and Old French, Middle French cost, Anglo-Norman and Middle French coust (masculine; French coût ) expenditure of effort, loss, or inconvenience incurred towards a particular end, expense, expenses, expenditure (all 12th cent. in Old French), probably < Old French coster cost v. Compare post-classical Latin costus , costum , costa , custus , custum (frequently from 12th cent. in British sources; from 13th cent. in continental sources). Compare also Old Occitan cost , masculine, costa , feminine (both 12th cent.), and also Catalan cost (c1330), Spanish costo (late 13th cent. or earlier), Portuguese custo (13th cent.), Italian costo risk, sacrifice (13th cent.), monetary outlay (a1306), all masculine. Compare cost v. and earlier costen v.²Borrowing into Germanic and Celtic. Compare also ( < Old French or post-classical Latin): Middle Dutch cost (also coste , feminine; Dutch kost ), Middle Low German kost , koste , Old High German kosta (Middle High German kost , koste , German Kosten , also Kost ), Old Icelandic kostr , Old Swedish koster (Swedish kost ), Old Danish, Danish kost , and also Irish costas ( < the Middle English plural form), Welsh cost (13th cent.). In many of the Germanic languages, this loanword appears to have been identified from an early date with the existing inherited noun < the Germanic base of cost n.² (compare similarly costen v.¹ beside costen v.²). Attestation in English. In sense 2 the word can be difficult to distinguish from cost n.² in some contexts. Earlier currency in this sense is perhaps implied by quot. a1325 at costful adj. (see discussion at that entry).

Etymology: < Anglo-Norman coste (in a 15th-cent. manuscript of a 1334 text; also 1334 in a contemporary manuscript as coutz , plural), specific use of coste side (see coast n.).

Etymology: < Anglo-Norman and Middle French coster (Anglo-Norman and Middle French couster , French coûter ) to require the expenditure of (a specified amount) for purchase, upkeep, etc., to require, entail, or cause (a specified sacrifice, suffering, loss, etc.), (all 12th cent. in Old French), (in legal use) to be to the cost of (early 14th cent. or earlier in Anglo-Norman), ultimately < classical Latin constāre to stand together, to stand still, to exist, to remain, continue, to stand firm, to be fixed or established, to be agreed upon, (with ablative or preposition) to consist of, be dependent on, be based on, (of sums, numbers) to be correct, balance, (in intransitive constructions, with the price in ablative or genitive) to cost, to be worth, in post-classical Latin also (as transitive verb) to cost (a specified sum) (from 12th cent. in continental sources) < con- con- prefix + stāre to stand (see stand v.). Compare earlier costen v.², cost n.³ Sense 5 probably shows a new formation < cost n.³Compare ( < Old French) post-classical Latin costare, custare to cost (from 13th cent. in British (frequently) and continental sources; apparently earlier in an undated inscription). Compare also Old Occitan costar (13th cent.), Catalan costar (14th cent.), Spanish costar (c1140; 1099 in a Latin document as †custar), Portuguese custar (13th cent.), Italian costare (a1236); and also ( < Old French or post-classical Latin) Middle Dutch costen to be valuable or expensive, to be worth or for sale at a particular price (Dutch kosten), Middle High German kosten to expend, spend, to involve suffering or sacrifice (German kosten).