Meaning A boy's name of Gaelic origin, it means "Son of Alasdair." Origin of Mac Alasdair Gaelic , Irish Popular Middle Names Pronunciation 🔊 Listen Mac Alasdair Similar Names Mac a’bhaird Mac a’bhiadhtaiche Mac Adhaimh Mac Ailean Mac an Aba Mac an Bharain Mac an Bhreatannai Mac Artuir Mac Asgaill Mac Bheathain Year by Year Popularity of Mac Alasdair