To use a trephine during surgery.
To perforate with a trephine.
A surgical instrument with a cylindrical blade used to remove a circular section of tissue, f.e. bone or cornea; a trepan.
To provide manual or mechanical breathing to a patient.
To provide with a vent.
To replace stale or noxious air with fresh.
To circulate air through a building, etc.
To expose something to the circulation of fresh air.
To expose something to public examination or discussion.
To shoot with a firearm; to pierce with bullets.