1. adverb [ADV after v, n ADV]
Herein means in this document, text, or book. [formal, written] ⇒ The statements and views expressed herein are those of the author and are not necessarily those of the Wilson Centre. ⇒ The argument contained herein takes exactly the opposite point of view. ⇒ Most of the experiences herein concern cancer.
2. adverb You can use herein to refer back to the situation or fact you have just mentioned, when saying it is something such as a problem or reason for something. [formal, written] ⇒ The point is that people grew unaccustomed to thinking and acting in a responsible and independent way. Herein lies another big problem.
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