Porezen (; in older sources also Porzen) is a dispersed settlement on the northern slopes of a hill also named Porezen above the BaÃÂa Valley in the Municipality of Tolmin in the Littoral region of Slovenia.
Porezen was attested in historical sources as Poworsona in 1523, Possenikh in 1560, Potporsna in 1591, and Podporsnam in 1633. The name is reconstructed with the prefix pod 'below' as *PodvrÃÂsÃÂno, referring to a location below a peak called *VrÃÂsni vrh or *VresnikâÂÂreferring to the treeless peak southeast of the village now also called Porezen (elevation: ), which was covered in heather ().