That is in an advanced state or condition; progressing towards maturity or completion. Chiefly predicative and barely distinguishable from the adv.

In a forward condition, advanced.

Advanced (in growth or progress). Also, of a season: Early.

Far on or ahead in any course of development; (hence) progressive, ahead of one's time.

Advanced, developed. Chiefly after most.

‘Getting on’, forward, advanced.