My client was making an accountable commitment -- to me, but really to himself. He pledged to "publish something new biweekly."
Whoah, I said. Is that "twice a week" or "every two weeks"?
In this case he meant "every two weeks" -- and I asked him to restate his commitment as "publish something new fortnightly." (A "fortnight" when not talking about the video game is a period of 14 days, aka two weeks. It's unambiguous.)
My Aspergers makes me acutely, even painfully, aware of ambiguity. A childhood of not understanding people will do that. It's served to make me, by others' estimates, one of the best communicators they know. One of my tricks is, avoid ambiguity and beware context dependence.
Whenever I or someone around me says something that [A] can be take two ways or [B] requires context to understand, my amygdala lights up. Yours should too.
It's far too easy to think we've communicated when we haven't.
Fred says "biweekly" and means "every two weeks" -- Barney hears "biweekly" and thinks "twice a week" -- they both nod and smile because they both were able to map a word to _a_ meaning, and now they mistakenly think they understand each other. Havoc will ensue.
If you want to become an exceptional communicator, remember what Manager Tools teaches: communication is what the listener does. As the speaker: avoid anything you should know is ambiguous; avoid anything that requires context to understand (or else provide context); actively check for understanding.