stumped
verb

- to be unable to answer a question or solve a problem because it is too difficult

(Cambridge Advanced Learner’s Dictionary)

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WORD ORIGIN

Etymology: The original meaning of the verb stump (circa 13th century) was to stumble over a tree or obstacle. The sense of walking clumsily or heavily is recorded in 1600. The sense of to be at a loss or to baffle is recorded in 1812. (Barnhart Concise Dictionary of Etymology)

"I’m stumped!".Who hasn’t thought it or said it out loud? Whether it’s trying to help your child with a physics homework problem or solving a television quiz show question, head scratching is a natural reflex. Even chimpanzees have been known to do it when given a task. Although it may have more to do with a puzzled view of the human race.

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SYNONYMS

addled, at sea, baffled, befuddled, bewildered, dazed, discombobulated, disconcerted, distracted, flummoxed, flustered, glassy-eyed, mixed up, nonplussed, perplexed, puzzled, spaced out

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ANTONYMS

astute, aware, brainy, conscious, discerning, hip, incisive, insightful, intuitive, judicious, keen, knowing, knowledgeable, observant, percipient, perspicacious, quick, rational, sagacious, savvy, sharp, sophic, tuned in, wise, wise to, with it

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SMUGGLE OWAD into a conversation:

"I’ve been trying to install this new software for over an hour. It has me totally STUMPED."