Kosmallagh Share definition Flag In Persian, It refers to a clumsy person. A person who has no stable pre-plan. It can be used to call a person who has done something very stupid. Yaroo gij mizad, kosmallagh. The guy was being so clumsy, Kosmallagh. Kosmallagh by Sharrareh December 27, 2010 Get the Kosmallagh mug.