a definition

stupid boy (pronunciation 'stü-p&d, 'boi) -- a boy who either purposefully or inadvertently does something rather unthoughtful, obtuse, and/or frustrating

e.g. a boy who
(1) hasn't called you in 9 months
(2) stopped calling you 9 months ago after the equivalent of a breakup, without actually having a relationship
(3) knows that you're INCREDIBLY stressed out
.... and yet calls you for the first time in 9 months just to get you to explain how to solve x=2^y for y, and THEN pronounces that it must be a good idea to call you regularly again since he doesn't hear profanities on the other end of the line.... = stupid boy.