Where does “smartassy” come from?

smartassy (English) comes from English smartass, from English -ass, from English ass, from Middle English asse, from Old English assa, from Old English assen, from Latin asinus, from Latin acinus — sharp.

Ancestry of “smartassy”, step by step

smartassy traces back through two separate lines of ancestry.

via English smartass

StepLanguageWordMeaning
1EnglishsmartassOne who is particularly insolent, who tends to...
2English-assUsed to intensify an adjective; Used to convert...
3EnglishassAny of several species of horse-like animals,...
4Middle EnglishasseAlternative form of axen
5Old Englishassaass, donkey
6Old Englishassenshe-ass
7Latinasinusa donkey, an ass; an ass, an idiot, a dolt, a...
8Latinacinusa berry, especially the grape; the seed of a...
9Latinaciessharp edge or point; battle line; battle,...
10Proto-Indo-Europeanh₂eḱ-sharp

via English Y

StepLanguageWordMeaning
1EnglishYA figure or mark in the shape of the letter Y; A...
2EnglishyuriA narrative or visual work featuring a romance or...
3Japanese百合lily
4Japanese連用形an inflectional category: the continuative or...
5Japanese見るto see, to watch, to observe, to look at...
6Japanesea dream; a vision; leaving reality to the state...
7Old Japanesea dream
8Japanesean order in biology: smaller than a class, bigger...
9Middle Chinese
Every word from Proto-Indo-European h₂eḱ-