hydromechanical
adjective
hy·dro·me·chan·i·cal ˌhī-drō-mi-ˈka-ni-kəl 
: relating to a branch of mechanics that deals with the equilibrium and motion of fluids and of solid bodies immersed in them
hydromechanics
ˌhī-drō-mi-ˈka-niks
noun, plural in form but singular in construction 
Example Sentences
Recent Examples on the Web The improper installation of an engine’s hydromechanical unit was at fault in the December helicopter accident near St. Cloud that killed three members of the Minnesota National Guard, according to a summary of an investigation released Wednesday. 
Reid Forgrave, Star Tribune, 6 Aug. 2020 These factors inform a large part of the calculus for the ongoing Air Force effort to replace the C-130s existing hydromechanical propeller control system with a new Electronic Propeller Control System (EPCS). Kris Osborn, Fox News, 25 June 2018
Reid Forgrave, Star Tribune, 6 Aug. 2020 These factors inform a large part of the calculus for the ongoing Air Force effort to replace the C-130s existing hydromechanical propeller control system with a new Electronic Propeller Control System (EPCS). Kris Osborn, Fox News, 25 June 2018 Word History
First Known Use
1797, in the meaning defined above