discernyoudaoicibaDictYouDict[discern 词源字典]
discern: [14] Discern, discreet, discrete, and discriminate all come ultimately from the same source, Latin discernere, literally ‘separate by sifting’, hence ‘distinguish’. This was a compound verb formed from the prefix dis- ‘apart’ and cernere ‘sift, separate’ (source of English crime and secret and related to crisis).

The derived noun discrīmen formed the basis of a new Latin verb discrīmināre, from which English gets discriminate [17]. (Closely related is decree [14], whose ultimate source is Latin dēcernere ‘decide’, also a derivative of cernere but with the prefix dē-, denoting removal.)
=> certain, crime, crisis, decree, discreet, discrete, discriminate, excrement, secret[discern etymology, discern origin, 英语词源]
discern (v.)youdaoicibaDictYouDict
late 14c., from Old French discerner (13c.) "distinguish (between), separate" (by sifting), and directly from Latin discernere "to separate, set apart, divide, distribute; distinguish, perceive," from dis- "off, away" (see dis-) + cernere "distinguish, separate, sift" (see crisis). Related: Discerned; discerning.