a suffix forming adjectives and nouns from verbs, occurring originally in French and Latin loanwords (pleasant; constant; servant) and productive in English on this model; -ant, has the general sense “characterized by or serving in the capacity of” that named by the stem (ascendant; pretendant), especially in the formation of nouns denoting human agents in legal actions or other formal procedures (tenant; defendant; applicant; contestant). In technical and commercial coinages, -ant, is a suffix of nouns denoting impersonal physical agents (propellant; lubricant; deodorant). In general, -ant, can be added only to bases of Latin origin, with a very few exceptions, as coolant .
< Latin-ant-, present participle stem of verbs in -āre; in many words < French-ant < Latin-ant- or -ent- (see -ent); akin to Middle English,Old English-and-, -end-, present participle suffix
British Dictionary definitions for -ant
-ant
suffix, suffix
1.
causing or performing an action or existing in a certain condition; the agent that performs an action: pleasant, claimant, deodorant, protestant, servant
Word Origin
from Latin -ant-, ending of present participles of the first conjugation
Word Origin and History for -ant
agent or instrumental suffix, from Old French and French -ant, from Latin -antem, accusative of -ans, present participle suffix of many Latin verbs.