The character or actions of wandering knights; the practice of wandering in quest of adventures.(noun)
Chivalry; a quixotic or romantic adventure or scheme.(noun)
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Use "knight-errantry" in a sentence
"It was time, he continued, “for the age of knight-errantry and mad-heroism to be at an end.”"
"It reminded one of the rude and chivalrous days of knight-errantry."
"'But, I believe,' he said, 'some genius of officiousness has today taken possession of me, for I began it upon a Quixote sort of enterprise, and a spirit of knight-errantry seems willing to accompany me through it to the end.'"