From WordNet (r) 2.0 (August 2003) [wn]:
fourth
adj : coming next after the third and just before the fifth in
position or time or degree or magnitude; "the
quaternary period of geologic time extends from the end
of the tertiary period to the present" [syn: 4th,
quaternary]
n 1: following the third position; number four in a countable
series
2: one of four equal parts; "a quarter of a pound" [syn:
one-fourth, quarter, fourth part, {twenty-five
percent}, quartern]
3: the musical interval between one note and another four notes
away from it
adv : in the fourth place; "fourthly, you must pay the rent on the
first of the month" [syn: fourthly]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Fourth \Fourth\, n.
1. One of four equal parts into which one whole may be
divided; the quotient of a unit divided by four.
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2. (Mus.) The interval of two tones and a semitone, embracing
four diatonic degrees of the scale; the subdominant of any
key.
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3. One coming next in order after the third.
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The Fourth, specifically, in the United States, the fourth
day of July, the anniversary of the declaration of
American independence; as, to celebrate the Fourth.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Fourth \Fourth\, a. [OE. fourthe, ferthe, feorthe, AS.
fe['o]r[eth]a, fr. fe['o]wer four.]
1. Next in order after the third; the ordinal of four.
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2. Forming one of four equal parts into which anything may be
divided.
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