1812, "soft, silly, weak-minded;" by 1836 as "foolishly sentimental," with -y (2) + spoon (n.) in a slang sense "silly person, simpleton" (1799), a figurative use of the eating utensil word, perhaps based on the notion of shallowness. Related: Spoonily; spooniness.
spoonbill
spoon-bread
spoonerism
spoon-feed
spoonful
spoony
spoor
sporadic
sporangium
spore
spork