'appredicate' originates from Latin, specifically formed from the prefix 'ad-' (appearing as 'ap-' before 'p') plus 'praedicare' meaning 'to proclaim, to declare', where 'ad-' meant 'to/toward' and 'praedicare' meant 'to proclaim or declare'.

'appredicate' developed via Medieval Latin forms such as 'appraedicare'/'appredicare' and entered Late Middle English usage in learned or theological contexts before stabilizing in modern English as 'appredicate'.

Initially it carried the sense 'to proclaim or declare (about a subject)'; over time the sense narrowed to 'to predicate or ascribe a quality' and is now used chiefly in specialized or archaic contexts to mean 'to ascribe as a predicate'.