extremal

[ ik-stree-muhl ]
/ ɪkˈstri məl /

adjective Mathematics.

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

Origin of extremal

First recorded in 1400–50; late Middle English. see origin at extremum, -al1
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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
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