| orthodox sleep | (n) a recurring sleep state during which rapid eye movements do not occur and dreaming does not occur; accounts for about 75% of normal sleep time, Syn. nonrapid eye movement, NREM, nonrapid eye movement sleep, NREM sleep |
| paradoxical sleep | (n) a recurring sleep state during which dreaming occurs; a state of rapidly shifting eye movements during sleep, Syn. rapid eye movement sleep, REM sleep, REM, rapid eye movement |