like a dream

:  a series of thoughts, images, or emotions occurring during sleep — compare rem sleep

:  an experience of waking life having the characteristics of a dream: such as

:  a visionary (see ¹visionary 2a) creation of the imagination :  daydream

:  to have a series of thoughts, images, or emotions while sleeping :  to have a dream (see ¹dream 1)

:  to indulge in daydreams or fantasies

:  to appear tranquil or dreamy (see dreamy 3a)