adjective
- indefinitely or exceedingly small; minute: infinitesimal vessels in the circulatory system.
- immeasurably small; less than an assignable quantity: to an infinitesimal degree.
- of, relating to, or involving infinitesimals.
noun
- an infinitesimal quantity.
- Mathematics. a variable having zero as a limit.
adjective
- infinitely or immeasurably small
- maths of, relating to, or involving a small change in the value of a variable that approaches zero as a limit
noun
- maths an infinitesimal quantity
1710 (1650s as a noun), “infinitely small,” from Modern Latin infinitesimus, from Latin infinitus “infinite” (see infinite) + -esimus, as in centesimus “hundredth.” Related: Infinitesimally.
Adjective
- Capable of having values approaching zero as a limit.
Noun
- A function or variable continuously approaching zero as a limit.