conspicuousness; prominence; distinctiveness
Often used for something that stands out visually, especially a striking color or unique quality. Common in phrases like 異彩を放つ (to stand out, to be strikingly different).
彼女の赤いドレスはパーティーで異彩を放っていた。
Her red dress stood out conspicuously at the party.
The painter's works have a distinctive prominence.
isolated gain in a weak market
Compound of 異 (い, 'different, unusual') and 彩 (さい, 'coloring, hue'), literally 'unusual coloring'. The meaning extended from a striking color to any conspicuous or distinctive quality.