olive oil: the pressed, refined product of the olive, used as food, fuel, medicine, cosmetic, sacred anointing, and the most vivid biblical image for abundance and joy
In the world of the Hebrew Bible this is simply the word for oil, and oil almost always means the product pressed from olives. One noun covers what we might split across several English words: the cooking oil people mixed into their bread and grain-gifts, the fuel they burned in their lamps, the cream they rubbed on their bodies, the substance poured on a new king's head, and the specially compounded sacred blend reserved for the worship tent and its priests. The unity of the word reflects the centrality of the product: the olive was the most economically important crop in the Iron Age Levant, and the oil it yielded was the densest caloric staple, the universal light source, the currency of trade with Phoenicia and Egypt, and the medium of the most weighty acts of sacred inauguration.
The word sits inside a web of related words built on an ancient root meaning "to be fat, rich, oily." The related adjective means "fat, robust, fertile," and the related verb (rare, always with a negative edge) means "to grow fat" in the sense of complacency. The noun simply names the product of that root, and this background explains why the same word can name the literal pressed liquid and the image of lavish abundance without any strain: both share the underlying idea of rich, yielding fatness. The standard lexicons disagree only about which sense to list first, the everyday "olive oil" or the older "fatness" at the root, but all agree the meaning is one many-sided word, not two unrelated ones.
A related word, יִצְהָר (yitshar), names the same substance at a different stage: the freshly pressed raw output of the press, almost always listed alongside grain and new wine as the triad of farm produce. Scholars and archaeologists have shown that שֶׁמֶן is the decanted, refined, marketable finished oil, what went to the palace as tax, to the temple as gift, to Tyre as trade, while יִצְהָר is the farm-gate yield. The Samaria pottery records of the eighth century BC note palace deliveries of "washed oil" (the finished product) and never יִצְהָר, confirming the distinction. A minority of scholars treat the two as largely literary synonyms that differ only in style, noting that the ancient Greek translation renders both with the same word; but the dominant reading, based on where each word appears, on inscriptions, and on the archaeology of olive presses, is the difference in stage of production.
The senses below are not different oils but the different roles one oil played, each carrying its own theological weight: the grain gift that honored YHWH as king, the lamp that symbolized his living presence in the tent, the blend that bore his distinctive fragrance, the pouring that made a man his anointed representative, the head anointing that expressed welcome and joy, and the images of overflow and abundance that became the most compact biblical figure for covenant blessing.