classroom

[klas-room, -roo m, klahs-] /ˈklæsˌrum, -ˌrʊm, ˈklɑs-/
noun
1.
a room, as in a school or college, in which classes are held.
2.
any place where one learns or gains experience:
The sea is the sailor's classroom.
Origin
1865-70, Americanism; class + room
British Dictionary definitions for classroom

classroom

/ˈklɑːsˌruːm; -ˌrʊm/
noun
1.
a room in which classes are conducted, esp in a school or college
Word Origin and History for classroom
n.

also class-room, 1811, from class (n.) + room (n.).