■ ordinal number
1》 constituting number three in a sequence; 3rd.
2》 ( a ~/one ~ ) each of three equal parts into which something is or may be divided.
3》 Music an interval spanning three consecutive notes in a diatonic scale, e.g. C to E ( major ~ , equal to two tones) or A to C ( minor ~ , equal to a tone and a semitone).
↘ Music the note which is higher by this interval than the tonic of a diatonic scale or root of a chord.
4》 Brit. a place in the ~ grade in an examination for a university degree.
Phrases
the ~ estate the ~ order or class in a country or society, comprising the common people.
~ time lucky (or US ~ time is the charm ) used to express the hope that one may succeed in the ~ attempt.
Derivatives
~ly adverb
Origin
OE thridda , of Gmc origin; related to three .