burglar vs cat burglar

burglar and cat burglar both are nouns.

Word	Noun	Adjective	Verb	Adverb
burglar	Yes	No	No	No
cat burglar	Yes	No	No	No

As nouns, cat burglar is a hyponym of burglar; that is, cat burglar is a word with a more specific, narrower meaning than burglar:

burglar: a thief who enters a building with intent to steal
cat burglar: a burglar who unlawfully breaks into and enters another person's house

Other hyponyms of burglar include housebreaker.

burglar (noun)	cat burglar (noun)
a thief who enters a building with intent to steal	a burglar who unlawfully breaks into and enters another person's house