extremal

[ ik-stree-muh l ]
/ ɪkˈstri məl /

adjective Mathematics.

of or relating to an extremum or the calculation of extrema: an extremal problem.

Origin of extremal

1400–50; late Middle English. See extrem(um), -al1

British Dictionary definitions for extremal

extremal
/ (ɪkˈstriːməl) /

noun

maths logic the clause in a recursive definition that specifies that no items other than those generated by the stated rules fall within the definition, as in 1 is an integer, if n is an integer so is n+1, and nothing else is