Sleep, slumber, drowse, doze, nap, catnap, snooze mean to take rest by a suspension of consciousness.
Sleep , the usual term, implies ordinarily the periodical repose of this sort in which men and animals recuperate their powers after activity, but it may imply such repose indulged in temporarily or at odd times.
Sleep can also refer to a condition (as dormancy, indolence, or death) felt to resemble true sleep.
Slumber implies sleeping but it has acquired connotations that usually distinguish it from sleep . When applied to persons it usually suggests a sleeping quietly and easily. In extended use it is likely to connote the repose of death and inactivity and suggest prolonged heavy sleep.
Drowse suggests a dull heavy condition of body and mind when one is falling asleep or is half asleep. In extension it implies a sluggishness that makes something move or act slowly.
Doze carries somewhat the same implications as drowse but the term often suggests a falling asleep, unintentionally or naturally, and does not emphasize a previous drowsy condition; often it suggests a falling asleep for a brief period or a drifting in and out of sleep, and it may imply a state of bewilderment when suddenly awakened.
Nap basically implies a taking of a short light sleep, especially in the daytime; in extended use it commonly implies an opposition to watch or be on the alert and does not necessarily suggest the taking of a nap but merely a relaxation of care or activity (as in preventing, protecting, or detecting).
Catnap implies a frequent taking of brief refreshing naps, usually at odd intervals fitted between one’s periods of activity.
Snooze , a somewhat casual or slangy term, may be used in place of nap and others of the preceding terms but without any emphasis on their distinctive or figurative connotations.