Wiktionary
alt. An optical instrument used for seeing inside tight spaces, consisting of a rigid or flexible tube with an optical relay inside so that the view through a lens or window at one end of the tube may be seen from a lens or eyepiece in the opposite end of the tube. n. An optical instrument used for seeing inside tight spaces, consisting of a rigid or flexible tube with an optical relay inside so that the view through a lens or window at one end of the tube may be seen from a lens or eyepiece in the opposite end of the tube.
Wikipedia
A borescope (occasionally called a boroscope, though this spelling is nonstandard) is an optical device consisting of a rigid or flexible tube with an eyepiece on one end, an objective lens on the other linked together by a relay optical system in between. The optical system in some instances is surrounded by optical fibers used for illumination of the remote object. An internal image of the illuminated object is formed by the objective lens and magnified by the eyepiece which presents it to the viewer's eye.
Rigid or flexible borescopes may be fitted with an imaging or video device. For medical use, similar instruments are called endoscopes.
Usage examples of "borescope".
The next step was to have holes cut into the bedrock with precision drills through which borescope cameras could then be inserted.
I borescoped the engines and found a shitload of damageblade notch breakouts and vane cracks.
I borescoped the engines and found a shitload of damage-blade notch breakouts and vane cracks.
I borescoped the engines and found a shitload of damage—blade notch breakouts and vane cracks.