Definition of "lean"
- verb
To hang outwards.
To press against.
To thin out (a fuel-air mixture): to reduce the fuel flow into the mixture so that there is more air or oxygen.
- adjective
Slim; not fleshy.
Having little fat.
Having little extra or little to spare.
Of a fuel-air mixture, having more air than is necessary to burn all of the fuel; more air- or oxygen- rich than necessary for a stoichiometric reaction.
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