Lazarus Kaplan is an English-language variant rendering of the name of the Belgian-American diamond cutter normally written as Lazare Kaplan (1883-1986). The form "Lazarus" appears in some early twentieth-century immigration records, US trade press articles of the 1920s and 1930s, and a number of early-period Lazare Kaplan International corporate filings before the firm standardised on the French form "Lazare". There is no separate person of significance in the diamond trade by the name "Lazarus Kaplan"; references to Lazarus Kaplan are essentially always references to the founder of Lazare Kaplan International.

For substantive biographical detail and an account of his career as a cleaver, his role in cutting the Jonker rough, and his commercial introduction of the Tolkowsky "Ideal" round brilliant to the American market, see the entry on Lazare Kaplan Sr. The point worth recording here is purely lexical: dealers, archivists and provenance researchers encountering the form "Lazarus Kaplan" in older trade documentation should treat it as a synonym, not as an indication of a different individual or a different firm.