As a considerable part of the Tain is occupied by connecting episodes with place-names, an explanation of some of the commonest elements in these may be of use to those who know no Irish:

Ath=a ford; e.g. Ath Gabla (Ford of the Fork), Ath Traiged (Ford of the Foot), Ath Carpat (Ford of Chariots), Ath Fraich (Fraech's Ford), etc.

Belat=cross-roads; e.g. Belat Alioin.

Bernas=a pass, or gap; e.g. Bernas Bo Ulad or Bernas Bo Cuailnge
(Pass of the Cows of Ulster, or of Cualnge).

Clithar=a shelter; e.g. Clithar Bo Ulad (shelter of the Cows of
Ulster).

Cul=a corner; e.g. Cul Airthir (eastern corner).

Dun= a fort; e.g. Dun Sobairche.

Fid=a wood; e.g. Fid Mor Drualle (Great Wood of the Sword-sheath).

Glass=a brook, stream; e.g. Glass Chrau (the stream of Blood),
Glass Cruind, Glass Gatlaig (gatt=a withe, laig=a calf).

Glenn=a glen; e.g. Glenn Gatt (Glen of the Withe), Glenn Firbaith
(Ferbaeth's Glen), Glenn Gatlaig.