1. to garnish; to accompany (as a card does a gift)
メッセージが添えられていますね。A message is attached, isn't it?
2. to add to as support; to prop up
左手を、支えるように右腕に添える。I place my left hand against my right arm to support it.
3. to accompany (as an aid, guide, translator, etc.)
4. to mimic; to imitate
5. to draw something near to oneself; to approach nearby