Where does “Ironside” come from?

Ironside comes from English iron and side, where side derives from Middle English side, Old English sīde, Proto-Germanic sīdǭ, and ultimately Proto-Indo-European sētis-, tracing back to the root sek-.

Ironside (English): A trooper in the Parliamentarian cavalry formed...

Definitions

  1. A trooper in the Parliamentarian cavalry formed...

Ancestry of “Ironside”, step by step

Ironside traces back through two separate lines of ancestry.

via English Side

StepLanguageWordMeaning
1EnglishSideA bounding straight edge of a two-dimensional shape
2Middle Englishsidecustom
3Old Englishsīdeside, flank
4Proto-West Germanic*sīdāside
5Medieval Latinsida
6Late LatinsetaAlternative form of saeta; hair, bristle; bristle
7Latinsaetaa bristle, hair on an animal; silk
8Proto-Italicsaitā
9Proto-Indo-Europeanséh₂ito-
10Proto-Indo-Europeansh₂ey-to bind, fetter
11Proto-Indo-Europeanseh₂-to satiate, satisfy

via English iron

StepLanguageWordMeaning
1EnglishironA common, inexpensive metal, silvery grey when...
2OssetianиронOssetian person; an Ossetian, speaking the Iron...
3OssetianирOssetians, the Ossetian nation; the speakers of...
4Proto-IranianwiHráhman
5Proto-Indo-IranianwiHrásman
6Proto-Indo-EuropeanwiHrósman; husband; warrior, hero
7Proto-Indo-Europeanweyh₁-to chase, pursue; to suppress, persecute
Every word from Proto-Indo-European seh₂-