The state of sleep where we dream, and it can be characterized by rapid movement of a human eye during the sleep, that usually happens 4-5 times over the night, it is basically a Dream State or D-State.

DREAM STATE (D-STATE): "The dream state of sleep where we have rapid eye movements."
Cite this page: N., Pam M.S., "DREAM STATE (D-STATE)," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/dream-state-d-state/ (accessed April 17, 2021).