Of a number n, Having the sum of divisors σ(n)<2n, or, equivalently, the sum of proper divisors (or aliquot sum) s(n).
Insufficient or inadequate in amount.
Lacking something essential; often construed with in.
A person who is deficient.
Of a number: equal to the sum of its proper divisors.
Fitting its definition precisely.
Having all of its parts in harmony with a common purpose.
Of flowers, having both male parts (stamens) and female parts (carpels).
Of a set: equal to its set of limit points, i.e. set A is perfect if A=A'.
Sexually mature and fully differentiated.
Made with equal parts of sweet and dry vermouth.
Excellent and delightful in all respects.
Representing a completed action.
Describing an interval or any compound interval of a unison, octave, or fourths and fifths that are not tritones.
Without fault or mistake; thoroughly skilled or talented.
A perfect score; the achievement of finishing a stage or task with no mistakes.
A leader of the Cathar movement.
The perfect tense, or a form in that tense.
To take an action, usually the filing of a document in the correct venue, that secures a legal right.
To make perfect; to improve or hone.