Greek Capital Letter Xi

Xi is the fourteenth letter of the Greek alphabet, represented in uppercase as three horizontal bars. In its original linguistic context, this character represents the consonant cluster ks, similar to the sound of the letter X in English. As a member of the Greek and Coptic script block, it serves as a fundamental building block for written Greek text, appearing in both ancient literature and modern correspondence.

Beyond its alphabetical role, this symbol is frequently encountered in specialized technical fields. It is a standard variable in mathematics and physics, often used to denote grand canonical ensembles or spatial coordinates. Because of its distinct appearance, the letter has also been adopted as a currency icon, most notably representing the cryptocurrency Ethereum. Its structured, geometric form makes it a common choice for branding in gaming and science fiction contexts where a futuristic aesthetic is required.