|Definition - An adjective — such as every or any — that qualifies members of a group separately instead of collectively.|
Example - Every good boy deserves ice-cream.
(The every is distributive. As opposed to all boys deserve ice-cream where all is not distributive.)
Oxford English Dictionary - The term's first citation is from 1824:
"The distributive adjective pronouns, each, every, either, agree with the nouns … and verbs, of the singular number only."
(L. Murray Eng. Gram. (ed. 5) I. 247 )