Acanthus (plural: acanthus, rarely acanthuses in English, or acanthi in Latin), in its feminine form acantha (plura: acanthae), is the Latinised form of the ancient Greek word acanthos or akanthos, referring to the Acanthus plant. It can also be used as the prefix acantho-, meaning "thorny". It may refer to:

• Acanthus (ornament), form in architecture and in leather carving derived from the plant