[app. intended to express the pronunciation (ęgzaṅ) of Fr. exempt.
Cf. EXAUN, occurring as a spelling of exempt in 1678; also exant (quot. 1655 below), used in the sense of EXEMPT sb. 4 a. The exempts or exons of the Yeomen of the Guard, according to Thoms Bk. of the Court, were first appointed in 1668.]
The ordinary title of the four officers of the Yeomen of the Royal Guard, styled corporals in their commissions (Thoms) and ranking below the Ensign; = EXEMPT sb. 4 b.
[1655. in Nicholas Papers (1892), II. 354. The Court gaue Moreland (Cromwells express) two Exants of ye guards to conduct him in safety.]
1767. Royal Calendar, 83. Yeomen of the Guards Exons [4 names follow].
1843. Macaulay, Ess., Mad. DArblay. It never occurred to the Exons, and Keepers of the Robes, that [etc.].
1873. Daily News, 19 June, 6/5. Colonel Bourke (the Exon in Waiting).
1891. New Army List, 132. Yeomen of the Guard Exons [4 names].