I have a bundle from my mother through her grandmother (origins in the UK). But for the life of me I can't come up with them on the fly.
I got in trouble this week for using the phrase "say-so" in a meeting. I had to repeat myself, slowly, "I can't just take someone's say-so on her performance."
Phrases most misused on this board, "Faithful and Discrete Discreet Slave", "tow toe the line", and "rank-and-file" (Meant to be used for the followers, not the leaders)
The most delightful terms raised on this board include Jehoober, Borg, Kingdom Hell, and "Cheese-and-Cracker Men".