From Longman Dictionary of Contemporary Englishworkhorsework‧horse /ˈwɜːkhɔːs $ ˈwɜːrkhɔːrs/ noun [countable] a person, machine, or vehicle that does a lot of work, especially when it is hard or boring The Hercules aircraft has been the workhorse of the air force for over 25 years.
Examples from the Corpus
workhorse• She wants to be known as a workhorse and not a clothes horse.• Cunningham is the team's defensive workhorse.• They are remarkably functional workhorses, two stroke, solid and very ugly.• He was also a great admirer of the weapon: The M60 was a real workhorse.• But the real workhorse of the Galapagos operation was the tiny sub called the Alvin.• Her strengths are her experienced pilots and her well-tested technology which make her a reliable workhorse.• The aircraft was the standard workhorse of Soviet medium-haul routes, a Tupolev 154 jet, six seats abreast.• The Boeing 707 used to be the workhorse of air travel.• The microcomputer which is usually recognized as the part with the keyboard on top is the workhorse of the system.From Longman Business Dictionaryworkhorsework‧horse /ˈwɜːkhɔːsˈwɜːrkhɔːrs/ noun [countable] a machine or vehicle that can be used to do a lot of workA new graphics software program is rapidly becoming the architect’s workhorse. 