'Tonometer' definitions:

Definition of 'tonometer'

(from WordNet)
noun
Measuring instrument for measuring tension or pressure (especially for measuring intraocular pressure in testing for glaucoma)

Definition of 'Tonometer'

From: GCIDE
  • Tonometer \To*nom"e*ter\, n. [Gr. ? a stretching, a tone + -meter.]
  • 1. (Physics.) An instrument for determining the rate of vibrations in tones. [1913 Webster]
  • 2. (Physiol.) (a) An apparatus for studying and registering the action of various fluids and drugs on the excised heart of lower animals. (b) An instrument for measuring tension, esp. that of the eyeball. [1913 Webster]