1. One: This is the most common meaning of "Mon". It comes from the Greek word "monos" and indicates "one" or "single". For example:
* Monocle: A single eyeglass.
* Monorail: A railway with a single rail.
* Monotheism: Belief in one God.
2. Month: This is a less common meaning, specifically used in words like "Monday" and "month". It derives from the Old English word "mōnað", meaning "moon".
3. Monk: This is another less common meaning, specifically referring to "monk" or "monastery". It comes from the Latin word "monachus", meaning "solitary".
4. Monetary: This meaning is specific to "Monetary", referring to money or currency. It is derived from the Latin word "moneta", which originally referred to a temple of Juno Moneta, where coins were minted.
Therefore, the meaning of "Mon" can be one, month, monk, or monetary, depending on the specific word it is used in.