We don't have synonyms for day room yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are dayroom, dead room and darkroom.
(n) :
Alternative spelling of dayroom. [A common room in a residential total institution such as barracks, psychiatric hospital, prison, or dormitory where the inhabitants can mingle and socialize.]
(n) :
Alternative spelling of dayroom. [A common room in a residential total institution such as barracks, psychiatric hospital, prison, or dormitory where the inhabitants can mingle and socialize.]