Wordnet 3.0
NOUN (1)
1.
a time period usually extending from Friday night through Sunday;
more loosely defined as any period of successive days including one and only one Sunday;
VERB (1)
1.
spend the weekend;
The Collaborative International Dictionary of English v.0.48:
Week-end \Week"-end"\, n.
The end of the week, usually comprising the period from
Friday evening to Monday morning, observed commonly as a
period of respite from work or school; as, to visit one for a
week-end; also, a house party during a week-end. Contrasted
to work days.
Note: Where work days continue throught Saturday morning, the
weekend starts on Saturday at noon.
[Webster 1913 Suppl. +PJC]
WordNet (r) 3.0 (2006):
weekend
n 1: a time period usually extending from Friday night through
Sunday; more loosely defined as any period of successive
days including one and only one Sunday
v 1: spend the weekend