Octa- : A prefix meaning eight. See Octo-.

Octa- : A combining form meaning eight; as in octodecimal, octodecimal, octolocular.

Example:
Could someone please provide directions from Route 50 OCTA to the Anaheim Metrolink and back again ?

Taxonomy
Orange County Transportation Authority, OCTA, Doing Business, Public Committees, Speakers Bureau, Riding, Fares, Passes, Metrolink, Streets, Bus Schedules, Board of Directors, Measure, Code of Conduct, Budget Crisis, Ready to Work, News and Media, Financial Information.

Defination from the web:
... Riding OCTA. Routes & Schedules. Fares & Passes. Community Programs. Access Service. Service Changes. Train. Metrolink Overview. Riding Metrolink. Lines & Stations ...