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.

Category: social gathering 
Words: place, club, outing, lettuce, group
lettuce

Category: temperature 
Words: cold, hot, cool, popular, relaxing
popular

Category: chocolate food 
Words: fudge, cookies, chocolate cake, smuggled, pudding

smuggled