Other forms: suckers
A sucker is one of the round pads on an octopus arm, or on any animal that grips by suction. Rows of suckers, the suckers grip, a squid's suckers.
The same word names the rubber pad on a bathroom hook — usually called a sucker or a suction cup — and, in gardening, a shoot growing up from a plant's roots, which growers cut off. Informally a sucker is somebody easily fooled: a sucker for a sad story. Note the saying about a sucker being born every minute, and the American use of sucker for any object at all: hand me that sucker.
1nounsuckerA round pad that grips by suction.
“The suckers leave rings on the glass.”
2nouneasilySomebody easily fooled.
“He is a sucker for anything with a free trial.”
3nounshootA shoot growing from a plant's roots.
“Cut the suckers off at the base or they take over.”
Too few real examples of this word to estimate which sense is commonest.
sucker is something that grips or draws.
Sucker is simply suck plus -er, one of the plainest formations in English. Every sense follows the action rather than a metaphor: the pad sucks, the shoot draws sap, and the person swallows what they are told.
Middle English
souker
English, today
sucker
From Middle English souker. From Middle English souker, sokere, sukkere, soukere, equivalent to suck + -er. Compare stq Suuger, West Frisian sûker (“sucker”), Dutch zuiger (“sucker”), German Sauger (“dummy; vacuum”).
Etymology from Wiktionary, CC BY-SA