Tom Collins vs collins

Tom Collins and collins both are nouns.

Word	Noun	Adjective	Verb	Adverb
Tom Collins	Yes	No	No	No
collins	Yes	No	No	No

As nouns, Tom Collins and collins are synonyms defined as:

Tom Collins and collins: tall iced drink of liquor (usually gin) with fruit juice

Tom Collins (noun)	collins (noun)
tall iced drink of liquor (usually gin) with fruit juice	tall iced drink of liquor (usually gin) with fruit juice