Abarim Publications' online Biblical Hebrew Dictionary
There are two identical root-verbs פתח (patah), whose ranges of meanings are clearly separate but, perhaps to a poetic eye, not without some overlap:
The root-verb פתח (patah I) basically means to open, and is perhaps a specialization of the verb פתה (pata), meaning to make wide. A third of the occurrences of our verb denotes the opening of the mouth (פה, peh), eyes, ears, hands or lips (Job 3:1, Psalm 51:17, Isaiah 50:5). Figuratively, this verb comes to mean to speak, to hear, to see etcetera. It may also mean to loosen or release, such as camels (Genesis 24:32), loins (Isaiah 45:1) or armor (1 Kings 20:11).
This verb's derivatives are:
- The masculine noun פתח (petah), meaning opening or doorway (Genesis 18:1, Psalm 24:7).
- The similar masculine noun פתח (petah), meaning opening (Psalm 119:130 only, used figuratively in the sense of unfolding).
- The masculine noun פתון (pithon), meaning opening (Ezekiel 16:63 and 29:21 only).
- The feminine noun פתיחה (petiha), denoting a drawn sword (Psalm 55:22, Psalm 37:14, Ezekiel 21:33). The edge of a sword was known as the "mouth" of it (Proverbs 5:4), so exposing the sword was known as "opening it's mouth". This noun is used in Psalm 55:22, Psalm 37:14 and Ezekiel 21:33 only.
- The masculine noun מפתח (miptah), meaning opening, utterance (Proverbs 8:6 only).
- The similar masculine noun מפתח (mapteah), meaning key (an instrument to open something with; Judges 3:25, 1 Chronicles 9:27 and Isaiah 22:22 only).
The verb פתח (patah II) means to carve or engrave. This verb is treated as separate from פתח (patah I) because linguists have distinguished similar verbs in other languages, but the meaning of carving texts in stone (Exodus 28:9, 1 Kings 7:36) comes very close to the meaning of exposing of the verb פתח (patah II).
This verb's sole derivative is the masculine noun פתוח (pittuah), meaning engraving (Exodus 28:11, 2 Chronicles 2:6).