Legislation - legislator - legislature

The verb'to legislate' means 'to pass (or enact) a law'. Three words derived from it have led to confusion.

• The people who legislate - those who pass the laws - are legislators. Examples are Members of Parliament in the UK, Congressmen (Representatives and Senators in the USA) and Senators in ancient Rome.
• The bodies that pass laws (e.g. Parliament, Congress and the Senate) are legislatures.
• The noun legislation has two slightly different uses.
  • It is a general non-count noun meaning 'the act of passing laws': "Parliament's function is legislation"
  • It is a collective noun meaning 'all (or a group of) the laws': "There is a comprehensive account of English legislation in Halsbury's Statutes, and "the legislation on drug use is inconsistent"

Legislator and legislature are listed by Fowler (1931) as a malaprop in the second group: these are two words with similar meanings and identical origins, which should not be muddled.