Lacking something essential; often construed with in.
Insufficient or inadequate in amount.
Of a number n, Having the sum of divisors σ(n)<2n, or, equivalently, the sum of proper divisors (or aliquot sum) s(n).
A person who is deficient.
Lacking in vigour; anemic, feeble.
Of a plant: intentionally grown in the dark.
Of an animal or person: having an ashen or pale appearance; also, haggard or thin; physically weak.
Of a plant or part of a plant: pale and weak because of sunlight deprivation or excessive exposure to sunlight.