lái'ér​bù​wǎng​fēi​lǐ​yě

reciprocity

来而不往非礼也 (來而不往非禮也) lái'ér​bù​wǎng​fēi​lǐ​yě
reciprocity
not to reciprocate is against etiquette; it is polite to return a favor or a visit
respond in kind
to treat someone in the same way they have treated you, often used in the context of retaliation

Frequency

Written text
0.109 per million

Sources

Definitions
CC-CEDICT
Frequency data
BCC Corpus (BLCU)