A more thorough explanation:

Term: REG.

Definition: Reg. is an abbreviation that can mean two things:

1. Regulation: A rule or set of rules made by a government or other authority to control or manage something. For example, traffic regulations are rules that drivers must follow to ensure safety on the road.
2. Register: A list or record of names or items. For example, a hotel register is a book where guests sign their names and provide information about their stay.

Both of these meanings are often used in legal or official contexts.

For example:

• The new reg. requires all businesses to provide a minimum wage of $15 per hour.
• Please sign the reg. before entering the building.

In the first example, "reg." is short for "regulation" and refers to a new rule that has been put in place. In the second example, "reg." is short for "register" and refers to a document that needs to be signed before entering a building.