Mark
as it is used in this verse, means,

Goal,
as in a race, contest,
battle, or other mission.
    Brethren,
I count not myself to have apprehended:
but this one thing I do,
forgetting those things which are behind,
and reaching forth unto those things
which are before,
I press toward the mark
for the prize of the high calling
of God in Christ Jesus...


Phillipians   
3:13-14