1.  The power which a horse exerts. [1913 Webster]

2.  A unit of power, used in stating the power required to drive machinery, and in estimating the capabilities of animals or steam engines and other prime movers for doing work. It is the power required for the performance of work at the rate of 33,000 English units of work per minute; hence, it is the power that must be exerted in lifting 33,000 pounds at the rate of one foot per minute, or 550 pounds at the rate of one foot per second, or 55 pounds at the rate of ten feet per second, etc. [1913 Webster]
" The power of a draught horse, of average strength, working eight hours per day, is about four fifths of a standard horse power." [1913 Webster]

3.  A machine worked by a horse, for driving other machinery; a horse motor. [1913 Webster]

N  measurement, admeasurement, mensuration, survey, valuation, appraisement, assessment, assize, estimate, estimation, dead reckoning, reckoning, gauging, horse power, metrology, weights and measures, compound arithmetic, measure, yard measure, standard, rule, foot rule, compass, calipers, gage, gauge, meter, line, rod, check, dividers, velo, flood mark, high water mark, Plimsoll line, index, scale, graduation, graduated scale, nonius, vernier, bathometer, galvanometer, heliometer, interferometer, odometer, ombrometer, pantometer, pluviometer, pneumatometer, pneumometer, radiometer, refractometer, respirometer, rheometer, spirometer, telemeter, udometer, vacuometer, variometer, viameter, thermometer, thermistor (heat) &c, barometer (air), anemometer (wind), dynamometer, goniometer, (angle) 244 meter, landmark, balance, scale, marigraph, pneumatograph, stethograph, rain gauge, rain gage, voltmeter (volts), ammeter (amps), spectrophotometer (light absorbance), mass spectrophotometer (molecular mass), geiger counter, scintillation counter (radioactivity), pycnometer (liquid density), graduated cylinder, volumetric flask (volume), radar gun (velocity), radar (distance), side-looking radar, (shape, topography), sonar (depth in water), light meter (light intensity), clock, watch, stopwatch, chronometer (time), anemometer (wind velocity), densitometer (color intensity), measurability, computability, determinability, coordinates, ordinate and abscissa, polar coordinates, latitude and longitude, declination and right ascension, altitude and azimuth, geometry, stereometry, hypsometry, metage, surveying, land surveying, geodesy, geodetics, geodesia, orthometry, altimetry, cadastre, astrolabe, armillary sphere, land surveyor, geometer, measuring, metric, metrical, measurable, perceptible, noticeable, detectable, appreciable, ponderable, determinable, fathomable, geodetical, topographic, topographical, cartographic, cartographical.

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