Heir adjectives are listed in this post. Each word below can often be found in front of the noun heir in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing HEIR.
acknowledged, apparent, be, born, catholic, chief, collateral, customary, direct, eventual, expectant, fellow, female
first, future, great, hopeful, immediate, infant, intellectual, intended, joint, last, lawful, legal, legitimate
lineal, little, lost, male, mine, natural, nearest, new, next, noble, old, only, other
own, political, possible, potential, precious, present, presumptive, principal, probable, proclaimed, prodigal, promised, proper
prospective, protestant, real, rich, right, rightful, royal, second, single, sole, spiritual, such, tender
third, true, undisputed, undoubted, universal, wealthy, worthy, young, youthful
Hope this word list had the adjective used with heir you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.