borrowed from Javanese kacapi, kecapi (phonetically kəčapi), going back to Old Javanese kacapi “kind of lute,” borrowed from Sanskrit kacchapī “lute,” feminine derivative of kacchapaḥ “tortoise, turtle” (probably from the resemblance of the lute's body to a tortoise shell), variant (probably conformed to kaccha- “bank, shore, marshy ground”) of kaśyapaḥ, going back to an Indo-Iranian noun of uncertain shape (perhaps *katsyapa-), whence Young Avestan kasiiapō “tortoise,” Khotanese khuysaa-, Persian kašaf, Ossetic (Iron dialect) xæfs “frog,” wærtdžɨn xæfs “turtle” (literally, “frog with shield”)

Note: Variants of the etymon, perhaps all eventually traceable to the Old Javanese word, are found in Indonesian Malay and a number of languages of the Sunda Islands and the southern Philippines. See Arsenio Nicholas, “Early Musical Exchange between India and Southeast Asia,” Pierre-Yves Manguin et al., editors, Early Interactions Between South and Southeast Asia, Singapore: Institute of Southeast Asian Studies, 2011, pp. 349-53.