Alga \a-lga, al-ga\ as a boy's name is a variant of Alger (Old English), and the meaning of Alga is "elf spear". The baby name Alga sounds like Algy, Alec, Alik, Alek, Alic, Algie and Algey. Other similar baby names are Algar, Alia, Alfa, Alta, Alva and Alba.