The period of time this condition prevails.
The progression of stages from conception to birth.
The condition of being pregnant; an instance of this.
The state of being productive, fertile or efficient.
The rate at which crops are grown on a standard area of land.
The ability to form new words using established patterns and discrete linguistic elements, as derivational affixes -ness and -ity.
The rate at which goods or services are produced by a standard population of workers.