The answer to the question of what gets larger the more you take away is a hole. The question is an example of a riddle, which is a puzzle with a double or hidden meaning.
The question is also an example of a conundrum, a type of riddle that relies on puns. Another type of riddle is an enigma, which is usually expressed in metaphorical language. Riddles were frequently part of Latin and Old English poetry as early as the fourth century. Riddles started as oral traditions. As of 2014, the word "riddle" can apply to many questions and answers that are considered witty or a play on words.