guard(redirected from on guard)
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a protective device.
mouth guard any of various removable intraoral appliances that protect the teeth and sometimes the lips and cheeks during contact sports.
1. To watch over so as to protect or maintain control.
2. A person or thing performing such a function.
A device for protecting something (e.g., a mouth guard or a face guard).
A removable dental appliance that covers one or both arches and is designed to minimize the damaging effects of bruxism, jaw and head trauma during contact sports, or any detrimental occlusal habits.See: nightguard; mouth guard