## CLOSED

### closed

#### Verb

closed

1. Sealed, made inaccessible or impassable; not open
2. Not operating or conducting trade
3. Not public.
closed source
a closed committee
4. Having an open complement.
5. Such that its image under the specified operation is contained in it.
The set of integers is closed under addition: $\forall x,y\in\mathbb{Z}\,x+y\in\mathbb{Z}$.
6. Lacking a free variable.

The above text is a snippet from Wiktionary: closed