Synonyms for Daydream (same or very similar meaning)
WordNet sense 1 (absentminded dreaming while awake):
reverie, daydreaming, oneirism, revery, air castle, castle in Spain, castle in the air
WordNet sense 2 (have dreamlike musings or fantasies while awake):
moon
WordNet sense 3 (have a daydream; indulge in a fantasy):
dream, stargaze, woolgather
From the ODE community, based on WordNet
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