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: type of sandwich 
Words: club, roll, doorstep, discothek, toast

SOLUTION: discothek

PROBLEM: Category: ocean 
Words: current, data sets, main, sea, wave

SOLUTION: data sets

PROBLEM: Category: physical property 
Words: heavy, fat, chunky, bulky, ugly

SOLUTION:
heavy