penny bank vs money box

penny bank and money box both are nouns.

Word	Noun	Adjective	Verb	Adverb
penny bank	Yes	No	No	No
money box	Yes	No	No	No

As nouns, money box is a hypernym of penny bank; that is, money box is a word with a broader meaning than penny bank:

penny bank: a child's coin bank (often shaped like a pig)
money box: a container (usually with a slot in the top) for keeping money at home

Other hypernyms of penny bank include bank, coin bank, savings bank.

penny bank (noun)	money box (noun)
a child's coin bank (often shaped like a pig)	a strongbox for holding cash
	a container (usually with a slot in the top) for keeping money at home