Simple Definition of pinhole
: a very small hole made by a pin or in some other way
Full Definition of pinhole
: a small hole made by, for, or as if by a pin
Examples of pinhole in a sentence
The water was leaking through a pinhole in the pipe.
<pinholes in a bedsheet will look like stars if you shine a light from behind it>
First Known Use of pinhole
Seen and Heard
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