When you send or respond to a text without fully thinking about the consequences of doing so. Similar to drunk texting but you're completely sober. Its more just plain impulsive
Example 1:

Father: You stayed out too late at that party last night; you're grounded for the next week
Son: Fuck you old man!
Father: make that the next month
Son: C'mon dad, that was my text reflex!

Example 2:

Texter Dude 1: Hey baby, you wanna go hookup behind the bleachers?

Texter Chick 1: Hell no you creeper! WTF is up with u? Drunk?
Texter Chick 1's friend: Yah, that was his text reflex
by TexterReflexer13 October 5, 2011
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