Abarim Publications' online Biblical Hebrew Dictionary
The verb משח (mashah) means to anoint, or even more general: to spread a liquid. In Jeremiah 22:14 the prophet speaks of "painting" a house bright red. In Isaiah 21:5 shield are "oiled". In Exodus 29:2 ritualistic unleavened cakes are "oiled".
It seems that this verb is employed where attention needs to be drawn; it does not simply denote a physical act but much rather a marking, a setting apart. It's no surprise therefore that the most common usage of this verb entails the ritual of "anointing" someone in office, and only the offices that had no earthly superior: the King of Israel (1 Samuel 16:3), a prophet (1 Kings 19:16, Isaiah 61:1) or a High Priest (Exodus 28:41).
One obvious derivation of this verb is משחה (missha), meaning anointing oil. This very special oil was manufactured according to a precise recipe (Exodus 30:22-25), and misuse or even duplication of it was strictly forbidden (Exodus 30:21-33). Whoever could call himself משיח (mashiah; our word Messiah) in Israel had had his head anointed with this highly guarded oil.
A much more frequently used word for oil in the Bible is the Hebrew noun שמן (shemen), which generally denotes olive oil, and which comes from the verb שמן (shamen), meaning to become fat. Although these words are also sometimes used in a ritualistic sense, they are much more commonly used for everyday practices, such as cooking or wound tending.
Ergo: the word שמן (shemen) denotes the "slippery stuff" and the word משחה (missha) denotes the "marking stuff".
The verb משח (mashah) yields a few other derivations which shed more light on the breadth of this verb's meaning:
- The noun משחה (mossha), means (consecrated) portion. It denotes a part of the peace offering that Israel was supposed to offer to God, consisting of an animal breast and thigh and its surrounding fat. The fat would go on the altar, but the breast and thigh would be "set apart" for Aaron and his sons (Leviticus 7:35).
- The noun ממשח (mimshah), which meaning is debated. HAW Theological Wordbook of the Old Testament notes that the meaning of this word is uncertain but proposes expansion, probably after the core meaning of the verb. BDB Theological Dictionary simply says dubious, and submits that this word only occurs in Ezekiel 28:14, in relation to a certain cherub. This passage is strongly debated because the author says it's about the king of Tyre, but it looks a lot like it's about satan. BDB translates these words with "cherub of expansion". The New American Standard Bible and the New International version simply read "anointed cherub".
- The noun and adjective משיח (mashiah), meaning anointed or anointed one, occurs about forty times in the Bible and may refer to priests (Leviticus 4:3-5, 4:16, 6:22) or kings (1 Samuel 2:10, 16:6) but also to an unspecified or abstract figure of reverence (1 Samuel 12:3-5). Our word occurs in implied plural in 1 Chronicles 16:22 and Psalm 105:15. HAW Theological Wordbook of the Old Testament notes that , "The Psalm literature especially regards mashiah as God's agent or vice-regent . . . but from the New Testament we learn that the meaning of mashiah in Psalm 2:2 can not be limited to a king about to be enthroned, but is a reference to the unique vice-regent Jesus Christ (Acts 13:32, Hebrews 1:5, 5:5)".