Of course the real reason they are called TIE fighters is that they 'looked like bow ties', and TIE was later a backronym (although I can't remember what source first names them as Twin Ion Engine craft).
Anyway, if it was up to you, what would you say those three letters stand for?
I have been partial to Tactical Interceptor Escort since this follows the convention of AT-AT (All Terrain Armored Transport) and other acronyms describing the function of the vehicle and not the actual technology of the engine. The IRD fighter, presumedly an earlier or close design of the TIE, is said to stand for Intercept/Recon/Defense, appearing in Han Solo at Stars End. ARC-170 is the Aggressve ReConnaisance fighter. It just seems odd to me to name an entire series of craft after its engines, no matter how 'revolutionary' a technology it is. Also Vader's TIE had four engines, not two, although it's possible there were two engines with two exhausts each.
Other suggestions for TIE:
Transport Interceptor Explorer (TIE Scouts)
Training Imperial Exercise
T- I- Enforcer
Just for fun:
Tiny Imperial Ejector
Any other suggestions?
Edited by GrimmyV