The Hebrew word ephes (אֶפֶס) denotes an end, extremity, or cessation — the point where something stops or ceases to exist. Used as an adverb it means 'nothing,' 'nought,' or 'only' (in the sense of 'nothing but'). It emphasizes the absolute nothingness or sole exclusivity of something.
Ephes is used powerfully in prophetic declarations of God's absolute sovereignty. 'There is none else, there is no God beside me' uses this word to assert the uniqueness and incomparability of Yahweh. All rival claims to deity are ephes — nothing, nought. This radical monotheism is foundational to Israel's faith and the New Testament confession that 'there is no other name under heaven by which we must be saved.'