frontispieceyoudaoicibaDictYouDict[frontispiece 词源字典]
frontispiece: [16] The final syllable of frontispiece has no etymological connection with piece. It comes from *spic-, a root denoting ‘see’ which is also represented in conspicuous and spectator. Here, as in the related auspices, its particular application is ‘divination by observation’. Added to Latin frōns ‘forehead’ it produced late Latin frontispicium, which originally meant ‘judgment of character through interpretation of facial features’.

Gradually it weakened semantically through ‘face’ to simply ‘front part’, and when English first acquired it, it was used for the ‘principal façade of a building’ (‘an indiscreet builder, who preferreth the care of his frontispiece before the maine foundation’, Richard Brathwait, English Gentleman 1630). By the 17th century, however, the word’s modern meaning ‘illustration facing the title page’ was becoming established. (Spellings based on an erroneous association with piece, incidentally, occur as early as the 16th century.)
=> auspices, conspicuous, front, inspect, spectator, spy[frontispiece etymology, frontispiece origin, 英语词源]
frontispiece (n.)youdaoicibaDictYouDict
1590s, "decorated entrance of a building," from Middle French frontispice (16c.), which is probably from Italian frontespizio and Medieval Latin frontispicium "facade," originally "a view of the forehead, judgment of character through facial features," from Latin frons (genitive frontis) "forehead" (see front (n.)) + specere "to look at" (see scope (n.1)). Sense of "illustration facing a book's title page" first recorded 1680s. The English spelling alteration apparently is from confusion with unrelated piece (n.).