Sheffer's stroke

noun

1. logic a function of two sentences, equivalent to the negation of their conjunction, and written p | q ( p and q are both not true) where p,q, are the arguments: p | q is false only when p,q are both true. It is possible to construct all truth functions out of this one alone

Word History and Origins

Origin of Sheffer's stroke¹

named after H. M. Sheffer (1883–1964), US philosopher