DAYDREAM
reverie, revery, daydream, daydreaming, oneirism, air castle, castle in the air, castle in Spain
(noun) absentminded dreaming while awake
dream, daydream, woolgather, stargaze
(verb) have a daydream; indulge in a fantasy
daydream, moon
(verb) have dreamlike musings or fantasies while awake; “She looked out the window, daydreaming”
Source: WordNet® 3.1
Etymology
Noun
daydream (plural daydreams)
A spontaneous and fanciful series of thoughts while awake not connected to immediate reality.
Coordinate terms: woolgathering, brown study, castles in Spain
Verb
daydream (third-person singular simple present daydreams, present participle daydreaming, simple past and past participle daydreamed or daydreamt)
To have such a series of thoughts; to woolgather.
Source: Wiktionary
Day"dream`, n.
Definition: A vain fancy speculation; a reverie; a castle in the air;
unfounded hope.
Mrs. Lambert's little daydream was over. Thackeray.
Source: Webster’s Unabridged Dictionary 1913 Edition