1 outside of a building
ADJ. elegant | plain
PREP. behind an/the ~ Hidden behind a plain exterior is a wonderful hotel. | on the ~ There is an abundance of fine sculpture, both on the exterior and inside.
2 sb's outward behaviour
ADJ. bland, bluff, calm, charming, confident, cool, glacial Her calm exterior hides very passionate feelings.
EXTERIOR + VERB belie, conceal, hide His bluff exterior belied a connoisseur of antiques.
PREP. behind sb's ~ Behind his cool exterior lurks a reckless and frustrated person. | beneath/underneath sb's ~ Beneath her charming exterior lies a very determined woman.