Informal; chiefly North American usage meaning ‘directly; exactly’, often in the phrase “plunk in the middle”.
Definitionen
Directly; exactly (informal). The cabin sits plunk in the middle of the woods.
Onomatopoeic use to represent the sound of something dropping or striking.
Definitionen
Used to imitate the sound of a sudden drop, impact, or plucking noise. "Plunk!" went the pebble as it hit the water.