-logycomb. form

earlier written -logie, an ending occurring originally in words adapted from Greek words in -λογία (the earliest examples, e.g. theology, having come through French -logie, medieval Latin -logia). These Greek words for the most part are parasynthetic derivatives; in some instances the terminal element is λόγος word, discourse (e.g. in τετραλογία tetralogy, τριλογία trilogy); more commonly it is the root λογ- (ablaut-variant of λεγ-, λέγειν to speak: cf. Logos n.). In the latter case, the nouns in -λογία usually denote the character, action, or department of knowledge proper to the person who is described by an adjective or noun in -λόγος, meaning either ‘(one) who speaks (in a certain way)’, or ‘(one) who treats of (a certain subject)’. Hence the derivatives in -λογία are of two classes, (1) those which have the sense of ‘saying or speaking’, examples of which are the words anglicized as battology, brachylogy, cacology, dittology, eulogy, palillogy, tautology; and (2) names of sciences or departments of study. As the words of the last-mentioned class have always a noun for their first element, and o is the combining vowel of all declensions of Greek nouns, the ending of these compounds is in actual use always -ολογία, becoming -ology comb. form in English. The names of sciences with this ending are very numerous: some represent words already formed in Greek, as theology, astrology; many represent formations which might legitimately have existed in Greek, as geology, zoology, psychology; others are of hybrid composition, as sociology, terminology, insectology. The modern formations in -logy follow the analogy of Greek formations in having o as the combining vowel; exceptions are petralogy (a form which some writers prefer to petrology because it shows the derivation from πέτρα rock, not from πέτρος stone) and mineralogy (French minéralogie) which may be viewed as a contraction for *mineralology. The suffix -ology is freely used in the formation of humorous nonce-words, some of which are illustrated below. All the modern formations in -logy may be said to imply correlative formations in -logical comb. form and -logist comb. form; in the case of some of the older words, the related personal designation ends in -loger comb. form or -logian comb. form. (Cf. -logue comb. form.) Hence logy n. = ology n.Apparently an isolated use.