Irish word >>mór<< 'BIG' and Romanian >>mare<< 'BIG'

Hello All,

I found out that the Irish word >>mór<< is cognate with Romanian word

>>mare<<.

I. >>mór<< Irish word -> adj big; adj great; adj large; adj large-
scale;
url: http://www.englishirishdictionary.com/dictionary?dict=ie&word=mor

II. >>mare<< Romanian word -> adj big; adj great; adj large; so
identical
url: http://dexonline.ro/search.php?cuv=mare&source=
Note: The DEX's Etymology for the Romanian word is Not OK:
Lat. mas doesn't fit phonetically and Latin maris means 'sea' so it
doesn't fit semantically (It's true that the 'Sea' is 'Big' but such a
basic notion as 'BIG' is cannot be constructed starting from the 'SEA'
concept as root concept...

So either the Romanian word >>mare<< 'big' is a Celtic word borrowed
by the Dacians (and next preserved in the Romanian Substratum) or the
Romanian word (having a Substratum (Dacian) origin) is cognate with
the Irish word.

Could somebody can post the full derivation from PIE of the Irish
word...

Thansk and Best Regards,
Marius