Cavalierness

a horseman, especially a mounted soldier; knight.
one having the spirit or bearing of a knight; a courtly gentleman; gallant.
a man escorting a woman or acting as her partner in dancing.
(initial capital letter) an adherent of Charles I of England in his contest with Parliament.
haughty, disdainful, or supercilious:
an arrogant and cavalier attitude toward others.
offhand or unceremonious:
The very dignified officials were confused by his cavalier manner.
(initial capital letter) of or relating to the Cavaliers.
(initial capital letter) of, relating to, or characteristic of the Cavalier poets or their work.
to play the cavalier.
to be haughty or domineering.
Historical Examples

adjective
showing haughty disregard; offhand
noun
a gallant or courtly gentleman, esp one acting as a lady’s escort
(archaic) a horseman, esp one who is armed
noun
a supporter of Charles I during the English Civil War Compare Roundhead
n.

1580s, from Italian cavalliere “mounted soldier, knight; gentleman serving as a lady’s escort,” from Late Latin caballarius “horseman,” from Vulgar Latin caballus, the common Vulgar Latin word for “horse” (and source of Italian cavallo, French cheval, Spanish caballo, Irish capall, Welsh ceffyl), displacing Latin equus (see equine).

Sense advanced in 17c. to “knight,” then “courtly gentleman” (but also, pejoratively, “swaggerer”), which led to the adjectival senses, especially “disdainful” (1650s). Meaning “Royalist adherent of Charles I” is from 1641. Meaning “one who devotes himself solely to attendance on a lady” is from 1817, roughly translating Italian cavaliere-servente. In classical Latin caballus was “work horse, pack horse,” sometimes, disdainfully, “hack, nag.” “Not a native Lat. word (as the second -a- would show), though the source of the borrowing is uncertain” [Tucker]. Perhaps from some Balkan or Anatolian language, and meaning, originally, “gelding.” The same source is thought to have yielded Old Church Slavonic kobyla.
adj.

“disdainful,” 1650s, from cavalier (n.). Earlier it meant “gallant” (1640s). Related: Cavalierly.

noun

A skillful boxer as distinct from a slugger or caveman (1920s+ Prizefight)