Definition of "licker"

When the back of the stamp is licked the first result is to leave on the tongue of the licker an unpleasant coating which demands the instant application of water to wash it off.

1913 March 20, The Sun, Sydney, page 6, column 6

[…] and enjoy wide-open views of St. Kilda beach and its passing parade of in-line skaters, skateboarders, dog walkers, and ice-cream lickers.

2019, Fodor's Essential Australia