Why is the ninth month called September?
1809, "to strut" (swanky, n., "attractive young fellow" is recorded from 1508), perhaps related to Middle High German swanken "to sway, totter," and Old High German swingan "to swing." Said to have been a Midlands and southwestern England dialectal word. The noun meaning "ostentatious behavior" is recorded from 1854; adjective sense of "stylish, classy, posh" is from 1913.
: the swank of his riding clothes (1920s+)verb
To behave ostentatiously; strut: I saw her swanking up the avenue in furs (1809+)
[origin unknown; perhaps fr Middle English swanken, ''to sway,'' cognate with German schwenken, ''to flourish'']