something that is defective, or that wants some of the properties found in other beings of the same kind.

**IMPERFECT Number**, is that whose aliquot parts, taken all together, do not make a sum that is equal to the number itself, but either exceed it, or fall short of it; being an abundant number in the former case, and a defective number in the latter. Thus 12 is an abundant imperfect number, because the sum of all its aliquot parts, 1, 2, 3, 4, 6, makes 16, which exceeds the number 12. And 10 is a defective imperfect number, because its aliquot parts 1, 2, 5, taken all together, make only 8, which is less than the number 10 itself.

**IMPERFECT Tense**, in *Grammar*, a tense that denotes some preterite case, or denotes the thing to be at that time present, and not quite finished; as scriberebam, "I was writing." See Grammar.