Otto Marcin Nikodym (3 August 1887 – 4 May 1974) (also Otton Martin Nikodým) was a Polish mathematician.

Immediately after his graduation in 1911, he started his teaching job at a high school in Kraków where he remained until 1924.

He eventually obtained his doctorate in 1925 from the University of Warsaw; he also spent an academic year (1926-1927) in Sorbonne.

[1] Nikodym was born in 1887 in Demycze, a suburb of Zabłotów (in modern-day Ukraine), to a family with Polish, Czech, Italian and French roots.

His work after coming to the United States centered on the theory of operators in Hilbert space, based on Boolean lattices, culminating in his The Mathematical Apparatus for Quantum-Theories.