Modifier Tone Letters

• Define a clear, consistent naming scheme for tone letters in your design system and document it for authors and developers.
• Keep a centralized reference lightweight and searchable to avoid drift across fonts and platforms.
• Provide a small CSS or font-feature set that makes tone letters easy to apply without duplicating glyphs.
• Include accessibility guidance, such as how screen readers should spell or describe modified letters.
• Test with real fonts and across common platforms to catch rendering gaps early.

Modifier Tone Letters are specialized diacritic-like marks used with base letters to indicate tonal or phonetic nuance. In typography and UI design, they appear as discrete glyphs and often need careful handling in fonts, CSS, and text shaping. Their main role is to convey nuance without expanding the character set dramatically.

Typical usage centers on scholarly, linguistic, or phonetic contexts, and in some locales they appear in education or language-learning interfaces. Designers should state when tone letters are essential and provide clear fallback options to keep content legible. Historically, these marks evolved to annotate tones and phonemes in compact textual notation, underscoring the need to balance typographic fidelity with usability.