Four-Sided Shape With One Pair of Parallel Sides
Puzzle 10 of Jokes and Gags Medium Pack
Question is: Four-Sided Shape With One Pair of Parallel Sides
and the answer is: TRAPEZOID
Word Meaning:
TRAPEZOID — (geometry, US, Canada) A (convex) quadrilateral with two (non-adjacent) parallel sides.
Definitions from Wiktionary.