safety lock vs safety bolt

safety lock and safety bolt both are nouns.

Word	Noun	Adjective	Verb	Adverb
safety lock	Yes	No	No	No
safety bolt	Yes	No	No	No

As nouns, safety lock and safety bolt are synonyms defined as:

safety lock and safety bolt: a bolt that cannot be moved from outside the door or gate

safety lock (noun)	safety bolt (noun)
guard consisting of a locking device that prevents a weapon from being fired	a bolt that cannot be moved from outside the door or gate
a bolt that cannot be moved from outside the door or gate