- rail (n.1)
- "bar," c.1320, from O.Fr. reille, from V.L. *regla, from L. regula "straight stick," dim. form related to regere "to straighten, guide" (see right). Used figuratively for "thinness" from 1872. Technically, railings (1471) are horizontal, palings are vertical.
- rail (n.2)
- "small bird," mid-15c., from O.Fr. raale (13c.), related to râler "to rattle," of unknown origin, perhaps imitative.
- rail (v.)
- "complain," 1460, from M.Fr. railler "to tease or joke" (15c.), perhaps from O.Prov. ralhar "scoff, to chat, to joke," from V.L. *ragulare "to bray" (cf. It. ragghiare "to bray"), from L.L. ragere "to roar," probably of imitative origin. See rally (2). Raillery "good-humored ridicule" is from 1653.