Definition of infinitesimal adjective from the Oxford Advanced Learner's Dictionary

 

infinitesimal

 adjective
adjective
BrE BrE//ˌɪnfɪnɪˈtesɪml//
 
; NAmE NAmE//ˌɪnfɪnɪˈtesɪml//
 
(formal)
 
jump to other results
extremely small synonym tiny infinitesimal traces of poison an infinitesimal risk Word Origin mid 17th cent.: from modern Latin infinitesimus, from Latin infinitus, from in- ‘not’ + finitus ‘finished, finite’, past participle of finire, from finis ‘end’, on the pattern of centesimal.
See the Oxford Advanced American Dictionary entry: infinitesimal