True North
Trump Card
T's And C's
T-Shirt Sizing
Turn Around
Turnaround Time
Twitterverse
Two Pizza Rule
Two Week Notice
Uberization
UML
UML Diagram
Uncharted Territory
Under-Index
Underpaid
Underscore
Unicorn
Unplanned Work
Unquit
Unregretted Attrition
Unspoken Rule
Upleveled
Upsell
Uptime Guarantee