Am"pli*tude (?), n. [L. amplitudo,
fr. amplus: cf. F. amplitude. See Ample.]
1. State of being ample; extent of surface or space;
largeness of dimensions; size.
The cathedral of Lincoln . . . is a magnificent structure,
proportionable to the amplitude of the diocese.
2. Largeness, in a figurative sense; breadth;
abundance; fullness. (a) Of extent of capacity
or intellectual powers. "Amplitude of mind." Milton.
"Amplitude of comprehension." Macaulay. (b)
Of extent of means or resources. "Amplitude of reward."
3. (Astron.) (a) The arc of
the horizon between the true east or west point and the center of the sun,
or a star, at its rising or setting. At the rising, the amplitude is
eastern or ortive: at the setting, it is western, occiduous, or occasive.
It is also northern or southern, when north or south of the equator.
(b) The arc of the horizon between the true east or
west point and the foot of the vertical circle passing through any star or
4. (Gun.) The horizontal line which measures
the distance to which a projectile is thrown; the range.
5. (Physics) The extent of a movement
measured from the starting point or position of equilibrium; -- applied
especially to vibratory movements.
6. (math.) An angle upon which the value of
some function depends; -- a term used more especially in connection with
Magnetic amplitude, the angular distance of a
heavenly body, when on the horizon, from the magnetic east or west point as
indicated by the compass. The difference between the magnetic and the true
or astronomical amplitude (see 3 above) is the "variation of the