Fourth \Fourth\, n.
1. One of four equal parts into which one whole may be
divided; the quotient of a unit divided by four.
[1913 Webster]
2. (Mus.) The interval of two tones and a semitone, embracing four diatonic degrees of the scale; the subdominant of any key. [1913 Webster]
3. One coming next in order after the third. [1913 Webster]
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. [1913 Webster]
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