Sauciness, n.
The quality or state of being saucy; that which is saucy; impertinent boldness; contempt of superiors; impudence. Your sauciness will jest upon my love. Shak.
Syn. -- Impudence; impertinence; rudeness; insolence. see Impudence.
Shades of meaning
Fernald has no entry of its own for sauciness; he lists it under impudence, pertness.
Where he writes about it:
Liveliness and sprightliness are pleasant and commendable; smartness is a limited and showy acuteness or shrewdness, usually with unfavorable suggestion; pertness and sauciness are these qualities overdone, and regardless of the respect due to superiors. — from pertness
Impertinence and impudence may be gross and stupid; pertness and sauciness are always vivid and keen. — from pertness