a.
1.
Costly, of great price, priceless.
2.
Very valuable, of great worth, of great value, inestimable, priceless.
3.
Dear, beloved, darling, very estimable, highly esteemed or valued, cherished, treasured, prized, idolized, adored.
4.
( Ironical. ) Good-for-nothing, worthless contemptible, base, despicable, pitiful.