TG tends to have multiple definations. It's like the word "Yankee". To those outside the community TG is an umbrella term covering everything from TV to TS. Within the community, there is a narrower defination as being some one that crossdresses for reasons somewhere between being strickly a crossdresser and someone who is Transsexual. ie TV, CD, TG, TS. That tends to be the defination within the community.
Like the word "Yankee", outside of the United States, we are all called Yankees, but within the United States, don't ever call someone from the South a "Yankee"!