oversit
To preside over, govern, rule; to control.
transitive
He is the Father of Gods and Men, the breeder and Maintainer of all the things whereof this worlde is compoſed: and yet for all that, he entreth not into them, but his power and prouidence ouerſitting them from aboue, atteine vnto all things, […]
To conquer, gain control or ownership of.
Let me, however, entreat of you, above all things, to remember my ball, and do not let them oversit the thing so as not to get to it.
To neglect, omit; to desist, refrain from, forbear.
archaic
And he greatly reproaches those who 'forget or oversit the time of housel,' […]
To spend too much time sitting.
intransitive
And Miriam Hopkins taboos fried foods. Asked how she keeps slender she answered, “Live sensibly, never overeat, oversleep or oversit.” That’s about the best reducing advice anyone could give. Next to overeating, oversitting is just about the worst way to destroy a lovely figure.
Where it comes from
From Middle English oversitten (“to gain possession of”), from Old English ofersittan (“to occupy, possess; forbear”), from Proto-West Germanic *ubarsittjan (“to sit over, occupy, preside over”), corresponding to over- + sit. Cognate with Middle Low German ōversitten, ȫversitten (“to attend, partake; advise, discuss; miss”), Middle Dutch oversitten (“to overstay; meet about, discuss”), Middle High German übersitzen (“to sit across from, occupy; disregard, neglect; exceed, miss”).
Adapted from the Wiktionary entry oversit (CC BY-SA 4.0).