All 4 Uses of

entail
in
Middlemarch

Uses with a meaning too rare to warrant foucs:

Dorothea, early troubling her elders with questions about the facts around her, had wrought herself into some independent clearness as to the historical, political reasons why eldest sons had superior rights, and why land should be entailed: those reasons, impressing her with a certain awe, might be weightier than she knew, but here was a question of ties which left them uninfringed.†
Chpt 4

During the months of this correspondence Mr. Brooke had continually, in his talk with Sir James Chettam, been presupposing or hinting that the intention of cutting off the entail was still maintained; and the day on which his pen gave the daring invitation, he went to Freshitt expressly to intimate that he had a stronger sense than ever of the reasons for taking that energetic step as a precaution against any mixture of low blood in the heir of the Brookes.†
Chpt Fin.

But when the entail was touched on in the usual way, he said, "My dear sir, it is not for me to dictate to you, but for my part I would let that alone.†
Chpt Fin. *

Definitions:

(1) (entail)
involve or require
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Entail also had a specialized meaning in law related to limiting the inheritance of property or order of succession. That sense is often seen in classic literature.