Spacing Modifier Letters
Not to be confused with Combining character, which modifies other characters, e.g. by adding diacritical marks.
Spacing Modifier Letters is a Unicode block containing characters for the IPA, UPA, and other phonetic transcriptions. Included are the IPA tone marks, and modifiers for aspiration and palatalization. The word spacing indicates that these characters occupy their own horizontal space within a line of text.History
The following Unicode-related documents record the purpose and process of defining specific characters in the Spacing Modifier Letters block:
