Where does “photounstable” come from?

photounstable (English) comes from English unstable, from English stable, from Middle English stable, from Anglo-Norman stable, from Latin stabilis, from Latin stare, from Latin sto, from Proto-Italic staēō.

photounstable (English): photochemically unstable

Definitions

  1. photochemically unstable

Ancestry of “photounstable”, step by step

photounstable traces back through two separate lines of ancestry.

via English unstable

StepLanguageWordMeaning
1EnglishunstableHaving a strong tendency to change; Fluctuating;...
2EnglishstableA building, wing or dependency set apart and...
3Middle Englishstablestable; Alternative form of stablie; Alternative...
4Anglo-Normanstable
5LatinstabilisThat stands firm; firm, steadfast, steady, sure,...
6Latinstarepresent active infinitive of stō; stand; to be
7LatinstoI stand; I stay, remain; I am
8Proto-Italicstaēōstand
9Proto-Indo-Europeansth₂éh₁yetito stand
10Proto-Indo-European*steh₂-

via English photo

StepLanguageWordMeaning
1EnglishphotoA photograph; A photo finish; To take a...
2EnglishphotographyThe art and technology of producing images on...
3Frenchphotographiephotography; photograph
4Ancient Greekφωτο-
5Ancient GreekφῶςAttic form of φᾰ́ος
6Proto-Hellenicpʰáos
7Proto-Indo-Europeanbʰéh₂os
8Proto-Indo-Europeanbʰeh₂-to shine, glow light; to speak, say
9Proto-Indo-Europeanbʰeh₂-s-ri-
Every word from Proto-Indo-European *steh₂-