Where does “murar” come from?

murar (Irish) comes from Irish -r, from Old Irish ro-, from Proto-Celtic ɸro-, from Proto-Indo-European per-, from Proto-Indo-European pr̥tós — passed , crossed.

murar (Irish): if... not, unless; if... was not, unless... was

Definitions

if... not, unless; if... was not, unless... was

Ancestry of “murar”, step by step

Step	Language	Word	Meaning
1	Irish	-r	A suffix added to certain preverbs and...
2	Old Irish	ro-	indicates a perfective aspect; indicates...
3	Proto-Celtic	ɸro-	before, in front of; in addition; to completion
4	Proto-Indo-European	per-	before, in front; first; to go through
5	Proto-Indo-European	pr̥tós	passed , crossed

Every word from Proto-Indo-European pr̥tós →Every word from Proto-Indo-European per- →Every word from Old Irish ro- →