What it did do was drag him down, as though my shot had dropped him into the dunk tank at the state fair.
In some basketball accounts of the mid 1900s, “dunk” simply meant to score in any way.
The Gatorade dunk is a perfect example, which has been a Super Bowl tradition since 1987.
1919, American English, from Pennsylvania German dunke "to dip," from Middle High German dunken, from Old High German dunkon, thunkon "to soak," from PIE root *teng- "to soak" (see tincture).
Basketball sense is first recorded 1937 as a verb, 1971 as a noun (earlier dunk shot). German-American Anabaptist sect of Dunkers (who baptize with triple immersion) first recorded by that name 1756.
[fr Pennsylvania German dunken, ''dip'']