protractor

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A semicircular instrument for measuring and constructing angles.
• noun Anatomy A muscle that extends a limb or other part.

from The Century Dictionary.

• noun One who or that which protracts. As applied to persons, also protractor.
• noun In anatomy, a muscle which protracts, or extends or draws a part forward: the opposite of retractor. See diagram under Echinoidea.
• noun An adjustable pattern, agreeing in proportion with particular measurements, used by tailors in cutting out garments.

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

• noun One who, or that which, protracts, or causes protraction.
• noun A mathematical instrument for laying down and measuring angles on paper, used in drawing or in plotting. It is of various forms, semicircular, rectangular, or circular.
• noun (Surg.) An instrument formerly used in extracting foreign or offensive matter from a wound.
• noun (Anat.) A muscle which extends an organ or part; -- opposed to retractor.
• noun An adjustable pattern used by tailors.

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

• noun One who, or that which, protracts, or causes protraction.
• noun A circular or semicircular tool for drawing or measuring angles.
• noun surgery An instrument formerly used in extracting foreign or offensive matter from a wound.
• noun anatomy A muscle that extends an organ or part; opposed to retractor.
• noun An adjustable pattern used by tailors.

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

• noun drafting instrument used to draw or measure angles