1. Of a particularly euphoric and loving disposition toward oneself and others, especially as might be induced by taking mood-altering drugs. Sometimes hyphenated. It's always great fun hanging out with the loved-up hippies at music festivals. Everyone at the party was all loved up and spaced out, so I knew they all must have taken some kind of illicit substance.

2. Very romantically infatuated; loving and feeling loved. Sometimes hyphenated. I think it's sweet seeing Carol so loved up with her new boyfriend. I hate coming to this part of town. It's always just filled with loved-up couples making kissy faces at each other.