Define the BELL of a stethoscope?

Question

diagram if necessary

Answer 1

The bell of the stethoscope is the side with a "bell or hollow cup shape" usually used to auscultate or to listen a lower frequencies sound. It makes the skin to vibrate when placed directly over it which then produce acoustic pressure waves traveling up to the listener's ears.

Here is the picture. The top part is the bell of the stethoscope.
http://www.flickr.com/photos/gavin1/115146772/

Answer 2

Define Stethoscope

Answer 3

The bell side. You have to press the stethoscope into the belly a bit.