Good and evil, right and wrong, become infinitesimal, ephemeral matters.
Let us conceive the zone in question to be divided into infinitesimal rings of equal area.
The acreage devoted to any other crop is practically infinitesimal, though in the eastern part more attention is paid to fruit-growing than perhaps in any other part of South Wales.
In 1883 he was chosen to succeed Henry Smith in the Savilian chair of geometry at Oxford, and there he produced his theory of reciprocants, largely by the aid of his "method of infinitesimal variation."
In mechanics we are specially concerned with the theory of infinitesimal displacements.