stymie
/ˈstʌɪmi/
verb
[with object]
informal
Prevent or hinder the progress of.
Origin
Mid 19th century (originally a golfing term, denoting a situation on the green where a ball obstructs the shot of another player): of unknown origin.
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Ted contemplated his putt. Bob's marker looked flat enough, but would it still deflect his ball and stymie the shot?