1. comparative form of plain; more simple, basic, or without decoration
2. comparative form of plain; more clear or obvious
3. comparative form of plain; less attractive in appearance

Examples

• The second dress was plainer than the first one.
• Could you make your instructions plainer?
• She chose the plainer of the two designs.
• His explanation was much plainer this time.
• The plainer room felt more comfortable to her.
• Nothing could be plainer than his disappointment.
• The plainer version costs less money.