Main Entry: cit·a·del

Pronunciation: \ˈsi-tə-d^əl, -ˌdel\

Function: noun

Etymology: Middle French citadelle, from Old Italian cittadella, diminutive of cittade city, from Medieval Latin civitat-, civitas — more at city

Date: 1562

1 : a fortress that commands a city
2 : stronghold <the nation's citadel of health research — Constance Holden> <a citadel of higher education>