Function timezoneAbbreviation

timezoneAbbreviation(
    timeZone?: string,
    date?: Date,
    abbreviations?: TimeZoneAbbreviations,
    locale?: LocalesArgument,
): string
Abbreviation of timeZone at date: the entry of abbreviations for the zone's UTC offset at that instant, else the locale's own name from timezoneName.
Parameters
- OptionaltimeZone: string
  IANA zone like "Asia/Tokyo"; the browser's zone when omitted
- date: Date = ...
  The instant whose offset picks the abbreviation; now when omitted
- Optionalabbreviations: TimeZoneAbbreviations
  Letter abbreviations keyed by offset
- Optionallocale: LocalesArgument
  Locale for the fallback name
Returns string
"JST", "EDT", or a fallback like "GMT+4"
Example
```
timezoneAbbreviation("Asia/Tokyo", new Date("2026-10-14T00:00:00Z"), { "+09:00": "JST" }); // "JST"
```
- Defined in packages/help/src/utils/date/date.ts:219