Transitive (to deceive) and intransitive/horticultural (to put forth shoots).
Definitions
To deceive or trick (someone), especially by gaining their trust. The con artist suckered the investors into buying worthless shares.
Of a plant: to send out shoots (suckers) from the base or roots. These roses will sucker heavily if the shoots are not removed early.
Used mainly attributively in compounds such as "sucker bet" to mean disadvantageous or tempting to the gullible.
Definitions
Slang, attributive: foolishly tempting or disadvantageous; likely to ensnare the unwary. Taking that kind of loan is a sucker move.