In this question we discussed the etymology of the word "snooker" as a noun, based on a game played on a pool table. But dictionary.com references a form of the word, "snookered" as a slang verb that means to "deceive, cheat, or dupe: to be snookered by a mail order company." (I wonder what the editor had against mail order companies?) Unfortunately, the word's origins are unknown to that site. Any ideas?
That said, the term is also used in the game itself to represent a position of difficulty. Wiktionary alludes to this in its entry:
Snookers are not that simple to achieve or to get out of. To snooker somebody would be to place an opponent in a difficult situation and to be snookered would imply that you are in a difficult situation. Snookering your opponent is part and parcel of the modern game. But I can see that it could be extended to mean to trick. Considering the game's British roots, it might have been considered ungentlemanly to resort to an intentional snooker (as the primary aim is to pot the balls), thereby lending the term connotations of deception and cheating.
An American equivalent would be the idiom, behind the eight ball.
As a Brit, I have never understood "snookered" to mean "to deceive, cheat, or dupe".
Chambers (www.chambersharrap.co.uk/) gives one meaning as "to thwart (a person or a plan)", which is what I've always understood it to mean.
Oxford Dictionaries (oxforddictionaries.com/definition/english/snooker?q=snookered#snooker__7) suggests that there are different British & US meanings:
British: leave (someone) in a difficult position; thwart
US: trick, entice, or trap