noun

1. the quality of being ample or the amount or degree to which a thing extends
2. an amount that is more than enough; abundance; fullness
3. scope or breadth, as of mind
4. the angular distance of a star from the true east or west point of the horizon, at the moment of its rising or setting
5. the extreme range of a fluctuating quantity, as an alternating current or the swing of a pendulum, generally measured from the average or mean to the extreme

Etymology: L amplitudo < amplus: see ample