› (of a person) thin and in good physical condition: Her body is lean, taut, athletic. › When you describe meat as lean, you mean that it does not have much fat in it: lean hamburger meat › A lean period is a time during which there is not enough of something, esp. money or food: It is a particularly lean year for science funding. › When you say that a company or business is lean, you mean that it has the fewest employees it needs to do its work.