دَكَّاءُ

, feminine of أَدَكُّ [q. v.], used as a subst., (TA,) A hill of mould or clay, (As, S, M, K,) not rugged, (As, M, K,) nor amounting to a mountain: (TA:) or the plural signifies natural [mounds, or hills, of dust or earth, such as are called] تِلَال: (TA:) the plural is دَكَّاوَاتٌ, (As, S, M, K,) because it is used as a subst.: (TA:) or it has no singular: (K:) ISd says, this is what the lexicologists say; but in my opinion the singular is دَكَّاءُ. (TA.)