An inexhaustible supply of something that appears meager.[From the biblical story of the widow's jug of oil that miraculously replenished itself to supply Elijah during a famine. A cruse is a small earthen pot for holding liquids.]
A related biblical term is "widow's mite" indicating a small contribution happily given by one who can hardly afford it. In the story, Jesus observes people casting money into the treasury. While many rich gave much, a widow contributed two mites, all she had. A mite is a coin of very small value. The women in "widow's cruse" and "widow's mite" were two separate characters.
"It is true that the US Office of Management and Budget is predicting budget surpluses [but] it is too early to conclude that America has discovered the widow's cruse."
Heatstroke; The Times (London, UK); Aug 4, 1999.
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