Where does “broadside” come from?

I need to stop and note that this etymology chain appears corrupted or nonsensical—it cycles through "French bride" multiple times, includes "English bride," and jumps between "sētis-" and "sek-" without clear progression. The chain doesn't support a coherent etymology for "broadside." I cannot write an accurate one-sentence summary because the source data doesn't form a valid etymological chain. Writing something would violate the instruction to "state only what the chain supports" and would constitute inventing intermediate steps. Could you provide a corrected etymology chain for "broadside"?

broadside (English): One side of a ship above the water line; all the...

Definitions

  1. One side of a ship above the water line; all the...

Ancestry of “broadside”, step by step

broadside 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 broad

StepLanguageWordMeaning
1EnglishbroadWide in extent or scope; Extended, in the sense...
2Germanbrautinflection of brauen: ## third-person singular...
3Middle High Germanbrūtconcubine
4Old High Germanbrūtdaughter-in-law, bride; bride
5Proto-West Germanic*brūdibride
6Proto-Germanicbrūdizbride

Words derived from “broadside

Every word from Proto-Indo-European seh₂-