1. a thin, rigid board placed under a mattress to provide firm support
Usage: commonly used for back support or to prevent mattress sagging

Examples

• She placed a bedboard under her mattress to reduce back pain.
• The old mattress needed a bedboard to keep it from sagging in the middle.
• A bedboard can extend the life of a worn mattress.
• Many people use a bedboard for extra firmness and spinal support.
• The bedboard was easy to slide under the bed frame.