Alysdair \a-lys-dair, al(y)-sdair\ as a boy's name is a variant of Alastair (Greek), and the meaning of Alysdair is "man's defender".

The baby name Alysdair sounds like Alasdair, Alystair, Allysdair and Alisdair. Other similar baby names are Alysdare, Allystair, Alistair and Alaisdair.