decretal noun & adjective. 
[dɪ'kri:t(ǝ)l] ME.[Late Latin decretale (whence also Old & mod. French décrétale), use as noun of neut. sing. of decretalis adjective (whence the English adjective), from Latin decret- pa. ppl stem of decernere DECERN: see -AL1.]A. noun.
1.  Ecclesiastical. A papal decree or decretal epistle; a document issued by a pope determining some point of doctrine or ecclesiastical law; in 
pl., the collection of such decrees forming part of the canon law. 
ME.2.  gen. A decree; an ordinance. 
L16.b. adjective.
1.  Pertaining to, of the nature of, or containing, a decree or decrees (esp. papal). 
L15.2.  Esp. of God's laws: imperative, inviolable. Also, decisive, definitive. Only in 
17. ■   decretaline adjective of or pertaining to the decretals 
E17-E18. ■   decretalist noun (a) a holder of the Calvinistic doctrine of the decrees of God; 
(b) = 
DECRETIST: 
E18. ■   decretally adverb in a decretal way; by way of decree: 
E17.  [TahlilGaran] English Dictionary ▲