way in the past; two decades ago; about twenty years ago
Refers to a time roughly twenty years ago, or more loosely a generation ago. Often used in contrast with 一昔 (about ten years ago) and 三昔 (about thirty years ago).
See also: 一昔
Twenty years ago, there were no smartphones.
The scenery of this town has completely changed from twenty years ago.
Standard kanji spelling.
Mixed kanji-kana spelling; also seen.
Compound of 二 (ふた, 'two') and 昔 (むかし, 'past, old times'). The reading ふたむかし follows the native Japanese counting system.