In the bad sense assurance is less gross than impudence, which is (according to its etymology) a shameless boldness. Assurance is in act or manner; impudence may be in speech.

J. C. Fernald, English Synonyms and Antonyms (1914)

Example sentences

audacity David had the audacity to ask Martha out on a date.
insolence Your insolence comes from your messianic complex.
impertinence Please accept my sincere apologies for my impertinence.
effrontery His effrontery turned everyone in the firm against him.
shamelessness Your shamelessness knows no bounds.
brazenness This series is a long essay on human malice, brazenness, and ruthlessness.

Popularity over time

Word	1850 → 2019	Trend
impudence		steady
audacity		rising
insolence		rising
impertinence		rising
effrontery		steady
shamelessness		rising

Use in printed books, per decade from 1850 to 2019.

By length

3 letters: lip¹
4 letters: face¹, gall¹, guff¹
5 letters: brass¹, cheek¹
8 letters: audacity⁴, boldness², rudeness², temerity⁴, chutzpah²
9 letters: assurance³, freshness², insolence³, brashness², flippancy
10 letters: disrespect³, incivility⁵, effrontery⁴, cheekiness, brazenness³
11 letters: presumption³, irreverence⁴
12 letters: impertinence
13 letters: shamelessness

The small number after each word is its number of syllables (audacity⁴ = 4 syllables).

In other languages

Français: impudence
Italiano: impudenza
Español: descaro
Deutsch: Dreistheit