Where does “spontaneousness” come from?

spontaneousness (English) comes from English spontaneous, from Latin spontāneus, from Latin -āneus, from Latin -eus, from Proto-Italic *-eos — Forms adjectives indicating being formed out of a material.

spontaneousness (English): The state or condition of being spontaneous;...

Definitions

  1. The state or condition of being spontaneous;...

Ancestry of “spontaneousness”, step by step

spontaneousness traces back through two separate lines of ancestry.

via English spontaneous

StepLanguageWordMeaning
1EnglishspontaneousSelf-generated; happening without any apparent...
2Latinspontāneusvoluntary, spontaneous
3Latin-āneusforming adjectives Of or pertaining to; -aneous
4Latin-eusargentum + API → argenteus; ferrum + API →...
5Proto-Italic*-eosForms adjectives indicating being formed out of a material

via English Ness

StepLanguageWordMeaning
1EnglishNessAn Ulster princess and the mother of Conchobar mac Nessa and Findchoem in the Ulster Cycle of Irish mythology. Daughter of Eochaid Sálbuide. Also the mother of Cormac Cond Longas by incest with Conchobar mac Nessa
2Middle Englishnesse
3Old Englishnæsnot, not at all; not; first/third-person singular...
4Proto-Germanicnasjąfoothill; headland; cape
5Proto-Indo-Europeannéh₂snose
Every word from Proto-Italic *-eosEvery word from Latin -eusEvery word from Latin -āneus