from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A semicircle.
- n. An instrument for measuring angles in surveying etc., resembling a protractor with an alidade, sights, and compass.
from the GNU version of the Collaborative International Dictionary of English
- n. An instrument for measuring angles, in surveying, etc. It resembles a protractor, but has an alidade, sights, and a compass.
from The Century Dictionary and Cyclopedia
- n. A simple instrument for measuring and indicating angles, sometimes used as a substitute for the theodolite.
demi- + circle. Compare French demi-cercle. (Wiktionary)