pityyoudaoicibaDictYouDict[pity 词源字典]
pity: [13] Latin pius ‘pious’, an adjective of unknown origin which gave English expiate and pious, had a noun derivative pietās. This has come into English in three distinct forms. First to arrive, more or less contemporaneously, were pity and piety [13], which were borrowed from respectively Old French pite and piete. These both developed from Latin pietās, and were originally synonymous, but they became differentiated in meaning before they arrived in English.

The Italian descendant of the Latin noun was pietà, which English took over in the 17th century as a term for a ‘statue of Mary holding the body of the crucified Christ’. Vulgar Latin *pietantia, a derivative of pietās, meant ‘charitable donation’. It has given English pittance [13].
=> expiate, piety, pious, pittance[pity etymology, pity origin, 英语词源]
pity (n.)youdaoicibaDictYouDict
early 13c., from Old French pite, pitet "pity, mercy, compassion, care, tenderness; pitiful state, wretched condition" (11c., Modern French pitié), from Latin pietatem (nominative pietas) "piety, loyalty, duty" (see piety). Replaced Old English mildheortness, literally "mild-heartness," itself a loan-translation of Latin misericordia. English pity and piety were not fully distinguished until 17c. Transferred sense of "grounds or cause for pity" is from late 14c.
pity (v.)youdaoicibaDictYouDict
"to feel pity for," late 15c., from Old French pitier and from pity (n.). Related: Pitied; pitying.