1) an electronic device which stores information (data), analyses it and produces further information as required (computer)

2) (of a country or part of it) required by treaty or agreement to have no military forces or equipment in it (demilitarized)

3) (not used of a person) bringing about the result required (effectual)

4) (an instance of) the use of less exact but less harsh words or phrases in place of words required by truth or accuracy (euphemism)

5) an action required by custom or rules (formality)

6) a list of meals that are available in a restaurant; a list of choices in a program to help the user find the information or facility required (menu)

7) a payment required for the use of a road, bridge, harbour etc; the costs suffered as a result of a war, disease, famine etc; (to cause a bell) to ring with slow, regular sounds (toll)