pigeon
noun
[ ˈpɪdʒɪn ]
• a stout seed- or fruit-eating bird with a small head, short legs, and a cooing voice, typically having grey and white plumage.
• a gullible person, especially someone swindled in gambling or the victim of a confidence trick.
• an aircraft from one's own side.
Origin:
late Middle English: from Old French pijon, denoting a young bird, especially a young dove, from an alteration of late Latin pipio(n- ), ‘young cheeping bird’ of imitative origin.
pigeon
noun
• archaic spelling of pidgin.
• a person's particular responsibility or business.
• "Hermia will have to tell them first, it's her pigeon"