Abarim Publications' online Biblical Hebrew Dictionary
The verb פחד (pahad) mostly means to fear, to tremble, to be very afraid, and on occasion it may mean to revere (Isaiah 60:5, Jeremiah 33:9, Hosea 3:5) or be impressed (Jeremiah 36:16 and 36:24). This verb is used for being in general dread (Deuteronomy 28:66, Proverbs 3:24, Isaiah 12:2), or dread for something or someone specific, usually YHWH (Isaiah 19:17, Job 23:15, Psalm 27:1). Its derivatives are:
- The masculine noun פחד (pahad), meaning dread or reverence with the same compass as the verb (Genesis 31:42, Deuteronomy 2:25, Isaiah 2:10, Job 4:14). It may also denote the object of fear; that which one fears (Job 31:23, Psalm 31:11).
- The feminine equivalent פחדה (pahda), used only in Jeremiah 2:19.
In Job 40:17 occurs the masculine noun פחד (pahad), which is identical to the one above, but really quite a different word. It's imported from Aramaic and also exists in Arabic. It means thigh. Still, the Hebrew language had its own words for thigh and the choice of the ancient author to deploy an Aramaic noun which happens to be identical to a Hebrew noun that means dread, is probably not arbitrary.