crustyoudaoicibaDictYouDict[crust 词源字典]
crust: [14] Latin crusta meant ‘hard outer covering, shell’ (it is related to a number of words, including ultimately crystal, denoting a hard surface caused by freezing). Old French acquired it as crouste (the modern French form croûte formed the basis of croûton, borrowed into English in the early 19th century), and passed it on to Middle English as cruste. Crusta formed the basis of the modern Latin adjective crustāceus ‘having a shell’, applied in the early 19th century to the crustacea or crustaceans. And a custard was originally a kind of pie enclosed in a crust.
=> croûton, crystal, custard[crust etymology, crust origin, 英语词源]
crust (v.)youdaoicibaDictYouDict
late 14c.; see crust (n.). Related: Crusted; crusting.
crust (n.)youdaoicibaDictYouDict
early 14c., "hard outer part of bread," from Old French crouste (13c., Modern French croûte) and directly from Latin crusta "rind, crust, shell, bark," from PIE *krus-to- "that which has been hardened," from root *kreus- "to begin to freeze, form a crust" (cognates: Sanskrit krud- "make hard, thicken;" Avestan xruzdra- "hard;" Greek krystallos "ice, crystal," kryos "icy cold, frost;" Lettish kruwesis "frozen mud;" Old High German hrosa "ice, crust;" Old English hruse "earth;" Old Norse hroðr "scurf"). Meaning "outer shell of the earth" is from 1550s.