Abbreviation of 列奧米爾/列奥米尔 (transliteration of French Réaumur) + 氏 (shì, “family”).
列氏
From Chinese 列氏 (Lièshì).
列(れっ)氏(し) • (resshi)
列氏 • (Yeolssi) (hangeul 열씨)