Where does “uncertainly” come from?

Uncertainly comes from English uncertain, from Latin certus (sure, determined) and unus (one), both ultimately from Proto-Indo-European roots óynos and ano-.

uncertainly (English): In an uncertain manner

Definitions

  1. In an uncertain manner

Ancestry of “uncertainly”, step by step

StepLanguageWordMeaning
1EnglishuncertainNot certain; unsure; Not known for certain;...
2Englishun-not; absent; lacking; not; negative; contrary to...
3Middle Englishun-
4Old Englishun-negation or absence of: un-, non-; bad; forms...
5Proto-West Germanicun-not, un-
6Proto-Germanicun-not, un-
7Proto-Indo-Europeann̥-not, un-
8Proto-Indo-Europeannenot
Every word from Proto-Indo-European neEvery word from Proto-Indo-European n̥-Every word from English un-