(that is to be kept) secret

secret

(of glances, threats etc) hidden; disguised

clandestine, underhanded

(in camps etc) a ditch (to be) used as a toilet

lavatory

not meant to be recorded or reported as official

confidential

a building, e.g. a shed, separate from the main building

toilet

a small building near to the main building

toilet

private; individual; of a particular person

private, individual

of, for the use of, concerning, one person or group, not people in general; a soldier with the lowest rank in the army

personal, intimate

beyond what is first seen or said

secret; pertaining to a hidden goal