Answer: thunk

AnswerCrossword Clue
THUNKHeavy landing sound
THUNKIdeated, to Li'l Abner
THUNKThought wrong?
THUNK"Who'da ... it?!"
THUNKIdeated, nonstandardly
THUNKVerb sung by the Scarecrow
THUNKHeavy, muffled sound
THUNKDull sound
THUNKConceived in a nonstandard way
thunkto make such a sound
thunkto make a sudden, muffled sound
thunkabrupt, dull sound