The adjective fastidious means giving a lot of attention and concern to details or showing high standards. It also means having a demanding attitude.

Synonyms are choosy, dainty, delicate, or finical.

The word origins from Latin (Mid 15th century) fastidiosus meaning “disdainful, squeamish, exacting”, fastidium meaning “loathing, squeamishness, dislike, aversion” which is of uncertain origin. Perhaps it comes from fastu-taidiom, a compound of fastus which means “contempt, arrogance, pride” and taedium meaning “aversion, disgust”. 

He is always so fastidious about all matters.

My mother is fastidious when it comes to grocery shopping.

Monica in the TV series F.R.I.E.N.D.S is the most fastidious and organized person.