'Jar of Oil' in the Bible

For thus says Yahweh, the God of Israel, 'The jar of meal shall not empty, neither shall the jar of oil fail, until the day that Yahweh sends rain on the earth.'"

The jar of meal didn't empty, neither did the jar of oil fail, according to the word of Yahweh, which he spoke by Elijah.

Elisha said to her, “What shall I do for you? Tell me, what do you have [of value] in the house?” She said, “Your maidservant has nothing in the house except a [small] jar of [olive] oil.”