Seir
Seir or SEIR may refer to:

Mount Seir, a mountainous region stretching between the Dead Sea and the Gulf of Aqaba
Seir the Horite, chief of the Horites, a people mentioned in the Torah
Sa'ir, also Seir, a Palestinian town in the Hebron Governorate in the West Bank 
Seir, a demon in the Ars Goetia
Southeast Indian Ridge (SEIR), is a mid-ocean ridge in the southern Indian Ocean
SEIR model, a compartmental model in epidemiology
Single-engine instrument rating, an aircraft pilot qualification

