Ma'anar ƙamus na kalmar "musibi" wani lamari ne ko yanayi mara kyau ko bala'i; rashin sa'a. Yana nufin wani yanayi ko al'amari da ake ɗauka a matsayin rashin sa'a ko rashin sa'a, wanda galibi yakan haifar da wahala, wahala, ko asara. Rashin sa'a na iya komawa ga kowane irin mummunan lamari ko yanayi, kamar rashin lafiya, rauni, asarar kuɗi, ko bala'in mutum.