I. noun suffix
Etymology: Middle English, from Anglo-French, from -ant, present participle suffix, from Latin -ant-, -ans, present participle suffix of first conjugation, from -a- (stem vowel of first conjugation) + -nt-, -ns, present participle suffix; akin to Old English -nde, present participle suffix, Greek -nt-, -n, participle suffix
a. one that performs (a specified action) ; personal or impersonal agent <claimant> <coolant> b. thing that promotes (a specified action or process) <expectorant> 2. one connected with <annuitant> 3. thing acted upon (in a specified manner) <inhalant> II. adjective suffix 1. performing (a specified action) or being (in a specified condition) <somnambulant> 2. promoting (a specified action or process) <expectorant>
New Collegiate Dictionary. 2001.