an entrenched fortification; a position protected by trenches.

or Intrenchment - generic term for any form of earthen fortification. In common usage, terms like breastwork, trench, entrenchment (intrenchment), curtain, and fieldworks were applied with little precision.

term occasionally misused in the context of treaties to refer to protection under the constitution. Aboriginal rights and treaty rights are protected under s.35 of the Constitution Act, 1982. Entrenchment of treaty rights does not mean that treaties become part of the Constitution.

the act or process of entrenching.