tīrthika (Sanskrit). Term meaning a ‘ford-maker’ used in Buddhist sources as a general designation for all those philosophical schools and traditions that are non-Buddhist. The sense of the term is obscure, but connotes the idea of teachings promulgated with the aim of fording the stream of cyclic existence (saṃsāra).

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)

Same as tīrthakāra.

Sarvastivada Abhidharma, Sanskrit-English Glossary, by Bhikkhu KL Dhammajoti