algometer

from The Century Dictionary.

• noun An instrument used in psychophysical determinations of the stimulus limen and differential limen of cutaneous or muscular pain. Also algesimeter.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Psychol.) An instrument for measuring sensations of pain due to pressure. It has a piston rod with a blunted tip which is pressed against the skin.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An instrument for measuring pain-inducing stimuli, and the sensitivity to such stimuli

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun device for measuring pain caused by pressure