close the gap

:  to move so as to bar passage through something

:  to block against entry or passage

:  to deny access to

:  a coming or bringing to a conclusion

:  a conclusion or end in time or existence :  cessation

:  the concluding passage (as of a speech or play)

:  an enclosed area

:  the precinct (see precinct 2a) of a cathedral

:  a narrow passage leading from a street to a court and the houses within or to the common stairway of tenements

:  having no openings :  closed

:  confined or carefully guarded

:  high

:  in a close position or manner

:  a break in a barrier (such as a wall, hedge, or line of military defense)

:  an assailable position

:  a mountain pass

:  to make an opening in

:  to adjust the space between the electrodes of (a spark plug)

:  to fall or stand open