what is fenestration
â¢ FENESTRATION (noun). The noun FENESTRATION has 2 senses: 1. the arrangement of windows in a building. 2. surgical procedure that creates a new fenestra to the cochlea in order to restore hearing lost because of osteosclerosis. Familiarity information: FENESTRATION used as a noun is rare.Dictionary entry details.ouns denoting acts or actions. Hypernyms (fenestration is a kind of...): operation; surgery; surgical operation; surgical procedure; surgical process (a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body). Domain category: