Meaning

noun a person who is gullible and easy to take advantage of

noun a shoot arising from a plant's roots

noun a drinker who sucks (as at a nipple or through a straw)

originFrom Middle English souker, sokere, sukkere, soukere, equivalent to suck (verb) + -er. Compare Saterland Frisian Suuger, West Frisian sûker (“sucker”), Dutch zuiger (“sucker”), German Sauger (“dummy; vacuum”).

Etymology from Wiktionary, CC BY-SA 3.0