1
general::
Phrase(s): forty winks
Fig. a nap; some sleep. • I could use forty winks before I have to get to work. • I need forty winks before I get started again.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
A brief nap, as in There's just time for forty winks before we have to leave. This expression supposedly was first recorded in 1828 and relies on wink in the sense of "sleep," a usage dating from the 14th century.
American Heritage Idioms