(TA) Equipment used to adapt integrated services digital network (ISDN) basic rate interface (BRI) channels to existing terminal equipment standards such as eia-232 and v.35. A Terminal Adaptor is typically packaged like a modem, either as a stand-alone unit or as an interface card that plugs into a computer or other communications equipment (such as a router or pbx). A Terminal Adaptor does not interoperate with a modem; it replaces it.

[ISDN faq].