1400-50;late Middle Englishsignet < Latincygnus, variant of cycnus < Greekkýknos swan; see -et
Examples from the web for cygnet
What you may have witnessed is the parents attempting to protect a cygnet.
British Dictionary definitions for cygnet
cygnet
/ˈsɪɡnɪt/
noun
1.
a young swan
Word Origin
C15 sygnett, from Old French cygne swan, from Latin cygnus, from Greek kuknos
Word Origin and History for cygnet
n.
c.1400, also signet before 17c., from Anglo-French, diminutive of Old French cigne, cisne "swan" (12c., Modern French cygne), from Latin cygnus, from Greek kyknos, perhaps from PIE *keuk- "to be white."