horsepower
Language: English
Part of speech: noun
Pronunciation: enpr: hôrsʹpou'ər
ipa: /ˈhɔɹsˌpaʊɚ/
enpr: hôsʹpou'ə
ipa: /ˈhɔːsˌpaʊə/
Forms: form: horsepowers
form: horsepower
Etymology: From horse + power: the unit was originally defined as the amount of power that a horse could provide.
Both non-metric and metric units of power were derived from effectively identical measurements of the power a draught horse could sustain over several hours, with the difference in watts solely due to different rounding errors to express that power in round numbers in the original non-SI units (ft·lbf/min and kgf⋅m/s respectively).
Senses: examples: text: Shillibeer's bus came in 1829 drawn by three horses. Later two horses were found sufficient to pull these closed wagonettes, which eventually had outside seats, and later on the substitution of a motor for horsepower.
ref: 1971, Gwen White, Antique Toys And Their Background, page 86:
text: The Sun Inn is an attractive black-and-white building, and has an old mounting block outside as a reminder of the days when horsepower meant four legs and a saddle.
ref: 1980, AA Book of British Villages, Drive Publications Ltd, page 150:
text: The wheel was to have been turned by horsepower, but it was adapted to be driven by a mill-wheel on the river Derwent […]
ref: 2003, Gavin Weightman, What the Industrial Revolution Did for Us, page 57:
glosses: Power derived from the motion of a horse.
examples: text: Equally I can stand in a station like Lucerne in Switzerland, and watch with ill-concealed admiration the majestic entry of one of the latest Gotthard "Ae 6/6" electrics, packing 6,000 horsepower within its 60 ft. of length and 121 tons of weight, with its sleek dark green sides and handsome stainless steel bands and front wings.
ref: 1955 April, Cecil J. Allen, “British Locomotive Practice and Performance”, in Railway Magazine, page 261:
text: As Quincy recovered from our one-block adrenaline burst, I gunned all 700 horsepower once more. Even with the pedal to the metal, the Exelero's sheer bulk caused a multisecond lag from the twin-turbo-charged V12's wind-up to actual launch.
ref: 2007 January 24, Sue Callaway, “Jonesing for a Maybach”, in CNN:
text: In the past, before the widespread adoption of SI units, the work that engines were capable of doing was compared with the work that horses could do – hence the term ‘horsepower’. Various people came up with various equivalencies, but the modern agreed definition is that 1 horsepower is 746 joules per second or 746 watts.
ref: 2012 March 22nd, David Blockley, Engineering: A Very Short Introduction (309), Oxford University Press, chapter 2: “The age of gravity – time for work”, page 20
synonyms: hp
glosses: A nonmetric unit of power with various definitions, commonly the mechanical horsepower, approximately equal to 745.7 watts.
synonyms: PS
glosses: Metric horsepower, a metric unit approximately equal to 735.5 watts.
examples: text: political horsepower
text: My patron who sent this to me to do a whole video on, you know, Convergence or whatever, being able to use this as a desktop, uh, replacement, or at least a desktop type thing, it’s impossible for me, I can’t do it, this device just doesn’t have that type of horsepower even to run itself, let alone actually run desktop Linux, it just can’t do it, I haven’t figured out how to do it.
ref: 2024 May 3, The Linux Cast, 8:35 from the start, in I Need to Apologize... This Device is Bad:
glosses: Strength, performance capability, specs, or similar.
Derived terms: brake horsepower
equivalent shaft horsepower
horsepower-hour
hydraulic horsepower
mechanical horsepower
metric horsepower
shaft horsepower
tax horsepower
thermal horsepower