A mail gateway that forwards electronic mail messages between two or more networks if they meet certain administrative criteria.
noun 1. a railroad car for carrying mail.
noun 1. a person, usually employed by the post office, who delivers mail.
[meyl-kach-er] /ˈmeɪlˌkætʃ ər/ noun, Railroads. 1. a device on a that, while the train is moving, picks up mailbags suspended beside the track.
[meyl-cheekt] /ˈmeɪlˌtʃikt/ adjective 1. (of certain fishes) having the cheeks crossed with a bony plate.