cav·a·lier / ˌkavəˈli(ə)r/ • n. 1. (Cavalier) hist. a supporter of King Charles I in the English Civil War. ∎ archaic or poetic/lit. a courtly gentleman, esp. one acting as a lady's escort. ∎ archaic a horseman, esp. a cavalryman.2. (also Cavalier King Charles) a small spaniel of a breed with a moderately long, noncurly, silky coat.• adj. showing a lack of proper concern; offhand: Anne was irritated by his cavalier attitude.DERIVATIVES: cav·a·lier·ly adv.

Cavalier a supporter of Charles I in the Civil War of 1642–9, a 17th-century Royalist. The word in this sense is recorded from the mid 17th century and is a special usage of the more general, ‘a horseman; a lively military man; a courtly or fashionable gentleman, a gallant, especially as an escort to a lady’; ultimately it derives (perhaps through French) from Italian cavaliere from Latin caballus ‘horse’.

The term as applied to the king's supporters by their opponents was originally derogatory. It was later increasingly used to indicate a style of life and social custom opposed to the repressive practices of the Roundheads.
Cavalier Parliament a name for the first Parliament of Charles II, following the Restoration in 1660 and noted for its support of the restored monarchy.

Cavalier (Fr. chevalier) Name adopted by the Royalists during the English Civil War in opposition to the Roundheads (Parliamentarians). The court party retained the name after the Restoration until superseded by Tory Party.

cavalier horseman; courtly gentleman, gallant XVI; Royalist XVII. — F. cavalier or its source It. cavaliere, deriv. of L. (Rom.) caballus horse (see prec.); see -IER.

cavalier. Elevated platform used as a look-out or a gun-emplacement in a fortress.