1. Plural of expander; devices or tools that increase in size or spread outward to fill a space.
Usage: Most common in technical, fitness, and construction contexts
2. Devices worn on the chest or arms to build muscle strength through resistance exercise.
Usage: fitness equipment
3. Mechanical or hydraulic devices used in construction or plumbing to enlarge holes or openings.
Usage: technical/construction

Examples

• The chest expanders helped him build upper body strength.
• Metal expanders are used to widen pipes during installation.
• She packed several hair expanders in her gym bag.
• The construction crew used hydraulic expanders to enlarge the tunnel.
• Foam expanders are common in packaging materials.
• He used expanders to stretch the leather boots to fit properly.