TASK DEFINITION: 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.
PROBLEM: Category: direction 
Words: remorseful, south, descending, downward, down

SOLUTION: remorseful

PROBLEM: Category: outdoor sport activity 
Words: whale, fish, raft, hiking, kayak

SOLUTION: whale

PROBLEM: Category: animal 
Words: fly, dive, walk, waggle, train

SOLUTION:
train