From WordNet (r) 3.0 (2006) :
UK
n 1: a monarchy in northwestern Europe occupying most of the
British Isles; divided into England and Scotland and Wales
and Northern Ireland; `Great Britain' is often used loosely
to refer to the United Kingdom [syn: United Kingdom,
UK, U.K., Britain, United Kingdom of Great Britain
and Northern Ireland, Great Britain]
From The Free On-line Dictionary of Computing (30 December 2018) :
uk
The country code for United Kingdom.
(1999-01-27)