I. noun Etymology: New Latin infinitesimus infinite in rank, from Latin infinitus Date: 1706 an ~ quantity or variable, II. adjective Date: 1710 taking on values arbitrarily close to but greater than zero, immeasurably or incalculably small , ~ly adverb
INFINITESIMAL
Meaning of INFINITESIMAL in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012