Webster's 1913 Dictionary
COMPASSES
COMPASSES Com "pass *es, n., pl.
Defn: An instrument for describing circles, measuring figures, etc. , consisting of two, or (rarely ) more, pointed branches, or legs, usually joined at the top by a rivet on which they move.
Note: The compasses for drawing circles have adjustable pen points, pencil points, etc. ; those used for measuring without adjustable points are generally called dividers. See Dividers. Bow compasses. See Bow-compass. -- Caliber compasses, Caliper compasses. See Calipers. -- Proportional, Triangular, etc. , compasses. See under Proportional, etc.
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