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2. TCBM
Abbreviation for "Trade Cards By Mail". Often used by Pokemon TCG Youtubers who trade cards to other players or Pokemon Youtubers in other cities/states/countries. Both parties send their cards, protected, in an envelope to each other and then post youtube videos about their successful TCBMs.
This is a video going over my current TCBMs with user007, user008, and user009.

I got some cool cards I needed for my deck in this TCBM with user007.
1. TCBM
That Could Be Misinterpreted

Similar to that's what she said, this phrase is more proper and a more general tool useful in turning any normal phrase into a sexual innuendo.
Person 1: "I like your box."
Person 2: "TCBM"

Person 1: "It's raining! I'm gonna get wet."
Person 2: "TCBM"
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