n. 25B6; plural noun BASICS, essentials, rudiments, foundations, basic principles, first principles, preliminaries; crux, crux of the matter, heart of the matter, essence, core, heart, base, bedrock; informal nuts and bolts, nitty-gritty, brass tacks, ABC.
FUNDAMENTALS
Meaning of FUNDAMENTALS in English
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012