knight_errantry has definitions from the field of medieval
1
[ noun ] quixotic (romantic and impractical) behavior

Synonyms

quixotism

Used in print

(Chicago Daily Tribune...)

His addle-brained knight-errant , self appointed to the ridiculous position in an age when armor had already been relegated to museums and the chivalrous code of knight-errantry had become a joke , is , as Cervantes no_doubt intended , a gaunt but gracious symbol of good , moving soberly and sincerely in a world of cynics , hypocrites and rogues .

Related terms

idealism

2
[ noun ] (medieval) the code of conduct observed by a knight errant who is wandering in search of deeds of chivalry
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