1. (of persons or animals) without much flesh or fat; not plump or fat; thin: lean cattle.
2. (of edible meat) containing little or no fat.
3. lacking in richness, fullness, quantity, etc.; poor: a lean diet; lean years.
4. spare; economical: a lean prose style.
5. Automotive. (of a mixture in a fuel system) having a relatively low ratio of fuel to air (contrasted with rich).
6. (of paint) having more pigment than oil.Compare fat (def 12).
"periods can be leanest."
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