To remove or clear a block or obstruction from.
In whist, to throw away a high card so as not to interrupt one's partner's long suit.
To free or make available.
To enable communication again, via telephone, instant messaging, etc., with (somebody previously blocked).
The removal of a block or blockage.
To release from a fold or pen.
To undo a folding.
To turn out; to happen; to develop.
To open (anything covered or closed); to lay open to view or contemplation; to bring out in all the details, or by successive development.
To reveal.
In functional programming, a kind of higher-order function that is the opposite of a fold.