bright line
n.— «“Bright lines,” as in “bright-line rule,” meaning a clear, unambiguous standard, are in demand in other contexts as well.» —“Bright lines and the search for certainty” by Ruth Walker Christian Science Monitor (Boston, Mass.) Dec. 15, 2005. (source: Double-Tongued Dictionary)
Further reading
Cat hair may be something you brush off, but cat hair is also a slang term that means “money.” In the same way, cat beer isn’t alcoholic — some people use cat beer as a joking term for “milk.” And imagine walking on a...
How do you pronounce species? Is it “spee-SEES” or “spee-SHEES”? Both are considered standard, but the spee-SHEES pronunciation is far more common. This is part of a complete episode.
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