intrench

verb

in·​trench in-ˈtrench 

less common spelling of entrench

transitive verb

1

a

: to place within or surround with a trench especially for defense

b

: to place (oneself) in a strong defensive position

c

: to establish solidly

entrenched themselves in the business

2

: to cut into : furrow

specifically : to erode downward so as to form a trench

intransitive verb

1

: to dig or occupy a trench for defensive purposes

2

: to enter upon or take over something unfairly, improperly, or unlawfully : encroach

—used with on or upon