1. a person or machine that applies a coating or covering to a surface
Usage: common in manufacturing and industrial contexts
2. a lightweight overcoat or jacket
Usage: informal, chiefly North American

Examples

• The factory hired a new coater to spray paint on the metal parts.
• The automated coater applies a protective finish to each product.
• She grabbed her coater before heading out into the cool evening.
• The coater machine ensures an even layer of varnish on the wood.
• He wore just a light coater over his shirt on the mild autumn day.