HEADY.This form of the English word has been displaced by headstrong. It occurs in 2Ti_3:1, where the same Gr. word is used as is translated rashly (RV [Note: Revised Version.] rash) in Act_19:36. Bp. Hall (Works, ii. 109) says, We may offend as well in our heddye acceleration, as in our delay.
Hastings' Dictionary of the Bible
Edited by James Hastings, D.D. Published in 1909
hed?i: The translation in the King James Version of προπετής, propetḗs, ?falling forward,? trop. ?prone,? ?ready to do anything,? ?precipitate,? ?headlong? (2Ti_3:4, ?heady, high-minded,? etc., the Revised Version (British and American) ?headstrong?; in Act_19:36, the only other place in the New Testament where propetēs occurs, the King James Version has ?rashly,? the Revised Version (British and American) ?rash?). ?Headstrong signifies strong in the head or the mind, and heady, full of one's own head? (Crabb, English Synonymes). ?Heady confidence promises victory without contest? (Johnson).
International Standard Bible Encyclopedia
PRINTER 1915.