whisperyoudaoicibaDictYouDict
whisper: [OE] Whisper comes ultimately from the prehistoric Germanic base *khwis-, which imitated a sort of hissing sound. This also produced German wispeln and wispern ‘whisper’, and with a different suffix it gave English whistle.
=> whistle
whisper (v.)youdaoicibaDictYouDict
Old English hwisprian "speak very softly, murmur" (only in a Northumbrian gloss for Latin murmurare), from Proto-Germanic *hwis- (cognates: Middle Dutch wispelen, Old High German hwispalon, German wispeln, wispern, Old Norse hviskra "to whisper"), from PIE *kwei- "to hiss, whistle," imitative. Transitive sense is from 1560s. Related: Whispered; whispering. An alternative verb, now obsolete, was whister (late 14c., from Old English hwæstrian), and Middle English had whistringe grucchere "a slanderer."
whisper (n.)youdaoicibaDictYouDict
1590s, from whisper (v.).