Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.
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Question: Category: physical activity 
Words: sprint, cow, duck, jog, squat

Answer: cow


Question: Category: ocean 
Words: late, wave, blue, current, drink

Answer: late


Question: Category: boxing terminology 
Words: hearts, knockout, deck, punch, tko

Answer:
hearts