oil spot
n.— «The movement would immediately extend into Vento and the Liguria and gradually embrace the surrounding regions “like an oil spot,” either through disorganizing and flanking operations of the militarily less organized Red elements of those districts, or by direct armed action.» —“Army Reports Reds Plot to Take Italy” by Drew Pearson Washington Post Sept. 8, 1947. (source: Double-Tongued Dictionary)
Further reading
What if, instead of being an inanimate object, a dictionary were alive? That’s the idea behind a lavishly illustrated new children’s book called The Dictionary Story (Bookshop|Amazon) by Oliver Jeffers and Sam Winston. This is part of a...
What exactly is a planet? Controversy over this question led to Pluto’s redefinition, along with a brand-new English word. And: Some people now use the phrase all the things! to mean and whatnot or you know what I mean. This new sense of all...