25B6; noun (informal) BASICS, essentials, fundamentals, substance, quintessence, heart of the matter; nub, crux, gist, meat, kernel, marrow; informal brass tacks, nuts and bolts.
NITTY-GRITTY
Meaning of NITTY-GRITTY in English
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012