Posed means arranged deliberately before the picture is taken. A posed photograph, posed for the camera, obviously posed.
It is set against candid, which catches people unaware, and the difference is visible — a posed group looks arranged because it is. In portraiture posing is the skill; in documentary it is a fault. Note posed as a past tense of pose in every sense, including posed a question and posed as somebody, which are separate uses.
1adjectiveposedArranged deliberately before the picture is taken.
“The wedding photos were all posed, so nobody looks natural.”
posed is a state of arrangement.