Gist
early 18th century: from Old French, third person singular present tense of gesir ‘to lie’, from Latin jacere . The Anglo-French legal phrase cest action gist ‘this action lies’ denoted that there were sufficient grounds to proceed; gist was adopted into English denoting the grounds themselves (gist (sense 2 of the noun)).
wiktionary
From Old French gist, from the verb gesir(“to lie down”), from Latin iaceō. Compare French gésir or gîte(“lodging”).
etymonline
gist (n.)
1711, "the real point" (of a law case, etc.), from Anglo-French legalese phrases such as cest action gist "this action lies," from Old French gist en "it consists in, it lies in," from gist (Modern French gît), third person singular present indicative of gésir "to lie," from Latin iacet "it lies," from iacēre "to lie, rest," related to iacere "to throw" (from PIE root *ye- "to throw, impel"). Extended sense of "essence" first recorded 1823.
