From WordNet (r) 2.0 (August 2003) [wn]:
interval
n 1: a definite length of time marked off by two instants [syn:
time interval]
2: a set containing all points (or all real numbers) between
two given endpoints
3: the distance between things; "fragile items require
separation and cushioning" [syn: separation]
4: the difference in pitch between two notes [syn: {musical
interval}]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Interval \In"ter*val\, n. [L. intervallum; inter between +
vallum a wall: cf. F. intervalle. See Wall.]
[1913 Webster]
1. A space between things; a void space intervening between
any two objects; as, an interval between two houses or
hills.
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'Twixt host and host but narrow space was left,
A dreadful interval. --Milton.
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2. Space of time between any two points or events; as, the
interval between the death of Charles I. of England, and
the accession of Charles II.
[1913 Webster]
3. A brief space of time between the recurrence of similar
conditions or states; as, the interval between paroxysms
of pain; intervals of sanity or delirium.
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4. (Mus.) Difference in pitch between any two tones.
[1913 Webster]
At intervals, coming or happening with intervals between;
now and then. "And Miriam watch'd and dozed at intervals."
--Tennyson.
Augmented interval (Mus.), an interval increased by half a
step or half a tone. Interval
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Interval \In"ter*val\, Intervale \In"ter*vale\, n.
A tract of low ground between hills, or along the banks of a
stream, usually alluvial land, enriched by the overflowings
of the river, or by fertilizing deposits of earth from the
adjacent hills. Cf. Bottom, n., 7. [Local, U. S.]
[1913 Webster]
The woody intervale just beyond the marshy land. --The
Century.
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