shamus vs house dick

shamus and house dick both are nouns.

Word	Noun	Adjective	Verb	Adverb
shamus	Yes	No	No	No
house dick	Yes	No	No	No

As nouns, house dick is a hyponym of shamus; that is, house dick is a word with a more specific, narrower meaning than shamus:

shamus: someone who can be employed as a detective to collect information and assist in criminal investigations
house dick: a private detective employed by a hotel or retail store

Other hyponyms of shamus include hotel detective, house detective, inquiry agent, store detective.

shamus (noun)	house dick (noun)
someone who can be employed as a detective to collect information and assist in criminal investigations	a private detective employed by a hotel or retail store