- a suffix forming nouns of action (birth) or abstract nouns denoting quality or condition (depth; length; warmth).
Origin of -th1
- a suffix used in the formation of ordinal numbers (fourth, tenth), in some cases, added to altered stems of the cardinal (fifth; twelfth).
Origin of -th2
- variant of -eth1: doth.
- (from verbs) indicating an action or its consequencegrowth
- (from adjectives) indicating a qualitywidth
- forming ordinal numbersfourth; thousandth
Word Origin and History for -th
suffix forming nouns (e.g. depth, strength, truth, etc.), from Old English -ðu, -ð, from Proto-Germanic *-itho, abstract noun suffix, from PIE *-ita (cf. Sanskrit -tati-; Greek -tet-; Latin -tati-, as in libertatem "liberty" from liber "free").
word-forming element making ordinal numbers (fourth, tenth, etc.), Old English -ða, from Proto-Germanic *-tha-, from PIE *-to-, also *-eto-, *-oto-, suffix forming adjectives "marking the accomplishment of the notion of the base" [Watkins] (cf. Sanskrit thah, Greek -tos, Latin -tus).