suffix
Suffix attached to nouns or verbs to indicate a person associated with that action, place, or characteristic. Common in compounds like 旅人 (たびびと) 'traveler' or 恋人 (こいびと) 'lover'. Not a free-standing word.
「旅人」の「人」は「と」と読む。
The 人 in 旅人 is read as と.
「恋人」は「こいびと」と読む。
恋人 is read as こいびと.
人 (じん) is used to indicate nationality or type of person (e.g., 日本人 'Japanese person'), whereas 人 (と) is used in a smaller set of native Japanese compounds.
The reading と for 人 is a native Japanese (kun'yomi) reading, used as a suffix in certain compounds. Its historical derivation is uncertain, but it is related to the word 人 (ひと) 'person'.