Across the world, Mairu (Mairu 
, ไม่รู้) is a rare unisex given name. The forename Mairu is characteristic of India, where it is a very rare largely female, but seldom male name, Tanzania, where it is a very rare boy's name, and Nigeria, where it is a very rare mostly male, but seldom female name. Likewise, Mairu is the last name as well as the forename.