Mendeleev

[men-dl-ey-uh f; Russian myin-dyi-lye-yef] /ˌmɛn dlˈeɪ əf; Russian myɪn dyɪˈlyɛ yɛf/
noun
1.
Dmitri Ivanovich
[dmyee-tryee ee-vah-nuh-vyich] /ˈdmyi tryi iˈvɑ nə vyɪtʃ/ (Show IPA), 1834–1907, Russian chemist: helped develop the periodic law.
Also, Mendeleyev, Mendelejeff.
British Dictionary definitions for Mendeleev

Mendeleyev

/Russian mɪndɪˈljejɪf/
noun
1.
Dmitri Ivanovich (ˈdmitrij iˈvanəvitʃ). 1834–1907, Russian chemist. He devised the original periodic table of the elements (1869)
Mendeleev in Science
Mendeleev
  (měn'də-lā'əf)   
Russian chemist who devised the Periodic Table, which shows the relationships between the chemical elements. He first published the Table in 1869 and continued to refine it over the next 20 years.