Glossary

Transition Area 
Controlled airspace of defined dimensions that extends upward from a specified altitude to the base of overlying controlled airspace.

TCA - Terminal Control Area

A Terminal Control Area (TCA) is a block of controlled airspace that surrounds a major airport or group of airports, designed to protect and manage high-density arrival and departure traffic.

This is a Canadian airspace designation (and ICAO standard), found in the Designated Airspace Handbook (DAH).
TCAs exist in both the real world and VATCAN FIR structures.

A TCA provides:

Controlled airspace for arrivals & departures
Aircraft climbing out or arriving are kept inside controlled airspace, typically from around 2,000–3,000 feet AGL up to 12,000–18,000 feet, depending on the airport.

Radar separation environment
TCAs are the airspace where Terminal (APP/DEP) controllers work.

Structured arrival/departure corridors
These accommodate STARs, SIDs, and flow traffic efficiently into the associated aerodrome(s).

In Canada, TCAs are usually designated as:

• Class C Major/Busy Airports or Terminal Areas ( CYYZ, CYUL, CYVR )

• Class D Secondary Airports or Terminal Areas ( CYHZ, CYBG , CYLW) 

• Class E Tesiary Airports or Terminal Areas ( CYQM , CYQX, CYKA, CYXE ) 

Terminal Radar Approach Control (TRACON)

A TRACON is a U.S. FAA term for a radar facility that provides terminal-area ATC services.
If you think in Canadian terms:

TRACON = U.S. equivalent of our Terminal Control Area 's - TCA 's (APP/DEP)

So for us, TRACON aligns with positions like CYHZ_APP, CYQM_APP, or any Canadian terminal controller working the arrival/departure environment.