Where does “jackleg” come from?

jackleg (English) comes from English Jack, from Middle English jakke, from Anglo-Norman jacke, from Middle French jaque, from Middle French jacques, from French jacques, from Latin Iacobus, from Ancient Greek Ἰάκωβος — heel of the foot; heel.

jackleg (English): Amateur, untrained; incompetent; Dishonest,...

Definitions

  1. Amateur, untrained; incompetent; Dishonest,...

Ancestry of “jackleg”, step by step

jackleg traces back through two separate lines of ancestry.

via English Jack

StepLanguageWordMeaning
1EnglishJackA placeholder or conventional name for any man,...
2Middle EnglishjakkeA padded coat, especially as light armour
3Anglo-Normanjacke
4Middle Frenchjaque
5Middle Frenchjacques
6Frenchjacquesplural of jacque; a stupid person; a jemmy or...
7LatinIacobusJacob; James; Saint James
8Ancient GreekἸάκωβος
9Ancient GreekἸακώβJacob
10HebrewיַעֲקֹבJacob
11Hebrewעָקֵבheel of the foot; heel

via English leg

StepLanguageWordMeaning
1EnglishlegA limb or appendage that an animal uses for...
2Middle Englishlegleg, limb; shank, shin; leg
3Old Norseleggrleg, stem
4Proto-Germaniclagjazleg, thigh
5Proto-Indo-European(ǝ)lak-
Every word from Hebrew עָקֵב