All 3 Uses of

chivalry
in
To the Lighthouse

Indeed, she had the whole of the other sex under her protection; for reasons she could not explain, for their chivalry and valour, for the fact that they negotiated treaties, ruled India, controlled finance; finally for an attitude towards herself which no woman could fail to feel or to find agreeable, something trustful, childlike, reverential; which an old woman could take from a young man without loss of dignity, and woe betide the girl—pray Heaven it was none of her daughters!†
Part 1 *

for there was in all their minds a mute questioning of deference and chivalry, of the Bank of England and the Indian Empire, of ringed fingers and lace, though to them all there was something in this of the essence of beauty, which called out the manliness in their girlish hearts, and made them, as they sat at table beneath their mother's eyes, honour her strange severity, her extreme courtesy, like a queen's raising from the mud to wash a beggar's dirty foot, when she admonished them so very severely about that wretched atheist who had chased them—or, speaking accurately, been invited to stay with them—in the Isle of Skye.†
Part 1

I lost my brooch—my grandmother's brooch," said Minta with a sound of lamentation in her voice, and a suffusion in her large brown eyes, looking down, looking up, as she sat by Mr. Ramsay, which roused his chivalry so that he bantered her.†
Part 1

Definitions:

(1) (chivalry)
the medieval principles governing knighthood and knightly conduct such as honor, kindness, bravery, and protection of the weak

or:

courtesy -- especially of men towards women
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Much less commonly, "chivalry" may reference a group of elite medieval fighters.