(~s)
1.
A ~ is a set of rules or instructions, for example the rules at the beginning of an examination paper. (FORMAL)
There was a firm ~ in the book about what had to be observed when interrogating anyone under seventeen.
N-COUNT
2.
A ~ is a title or heading under which something operates or is studied. (FORMAL)
The aid comes under the ~ of technical co-operation between governments.
= title, heading
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