Dictionary.com
definitions

Lobachevsky

[loh-buh-chef-skee; Russian luh-buh-chyef-skyee]
noun
  1. Ni·ko·lai I·va·no·vich [nyi-kuh-lahy ee-vah-nuh-vyich] /nyɪ kʌˈlaɪ iˈvɑ nə vyɪtʃ/, 1793–1856, Russian mathematician.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for lobachevsky

Lobachevsky

noun
  1. Nikolai Ivanovich (nikaˈlaj iˈvanəvitʃ). 1793–1856, Russian mathematician; a founder of non-Euclidean geometry
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012