Hash sign is a well-known symbol, also called the pound sign or the octothorpe. It is used to mark numbers, identify entries in a list or group, and represent various meanings and contexts. Some synonyms for hash sign include numeral sign, cross-hatch, tic-tac-toe board, grid, crisscross, lattice, and mesh. These synonyms are often used in different contexts, such as in music notation, coding, and social media. For instance, in coding, hash sign is used to indicate metadata or anchor links. On social media, it is used to tag keywords and topics for easy tracking and organization. Regardless of the synonym used, the hash sign remains a versatile and ubiquitous symbol in modern communication.