Interesting... in my area (NYC) I only hear people say it to mean 14 days. I suppose the rationale is to think of "bi" as "two" (precisely as you'd do for bicyc

Interesting... in my area (NYC) I only hear people say it to mean 14 days. I suppose the rationale is to think of "bi" as "two" (precisely as you'd do for bicycle, bisexual, binomial, etc.) rather than as "twice" and then the ambiguity disappears. Counterexample supporting ambiguity: the word bisect, which means two sections, but can quite easily also be thought of as halving!