antiquity; previous era
Refers to a past age or former times, often in historical or literary contexts.
I study the civilizations of antiquity.
Ruins from a previous era were discovered.
現代 means 'the present age', the direct opposite of 前世's 'former era'.
Written the same as 前世 (ぜんせい, 'a past era'), but read ぜんせ it instead means 'a previous life' in reincarnation.
Compound of 前 (zen, 'previous') and 世 (sei, 'world' or 'era'). The exact historical derivation is uncertain.