noun
propositional function; sentential function
Technical term in logic and mathematics. Refers to an expression containing variables that becomes a proposition when the variables are replaced with specific values.
「xは偶数である」は命題関数の一例です。
"x is an even number" is an example of a propositional function.
Compound of 命題 (proposition) and 関数 (function), likely a calque from English 'propositional function'.