- with or as if with a sudden muffled thud: The huge stone hit the water kerplunk.
Origin of kerplunk
First recorded in 1885–90;
see origin at ker-
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for kerplunk
Then I began to fly—drift down, and all of a sudden, kerplunk, I fell out of bed.
"That colour of hair and eyes always knocks me kerplunk," observed Hollanden softly.