1. a substance or tool that makes something less tight or less firmly attached

Examples

• Apply the rust loosener to the bolts before trying to remove them.
• This muscle loosener helps relieve tension after exercise.
• The mechanic used a penetrating loosener on the stuck parts.
• Hair loosener products can help relax tight curls.
• The soil loosener made it easier to plant the seeds.
• Use a screw loosener if the fasteners won't budge.