by-line vs hobby

by-line and hobby both are nouns.

Word	Noun	Adjective	Verb	Adverb
by-line	Yes	No	No	No
hobby	Yes	No	No	No

As nouns, by-line and hobby are synonyms defined as:

Other synonyms of by-line include avocation, pursuit, sideline, spare-time activity.

by-line (noun)	hobby (noun)
an auxiliary activity	an auxiliary activity
a line giving the name of the writer of a story or article	small Old World falcon formerly trained and flown at small birds
	a child's plaything consisting of an imitation horse mounted on rockers; the child straddles it and pretends to ride