It’s safe to come by (6)
I believe the answer is:
secure
This clue is a double definition.
'it's safe' is the first definition.
(similar in meaning)
'come by' is the second definition.
(thesaurus)
'to' acts as a link.
(Other definitions for secure that I've seen before include "land" , "Fix; safe" , "Reliable; firmly fixed" , "Safe, protected" , "Make safe or fasten" .)