Near.
The synonym of designated is specific
The synonym of optimize is perfect.
the synonym for wedge is xhahdghasdgah
Level is a palindrome that is a synonym for horizontal
a synonym for similar is alike.
Near.
A close (but not perfect) synonym would be companion, or guardian.
It is pretty much an exact synonym, yes.
A synonym of introduce is acquaint. An antonym of introduce is close.
Close Together
Close by / At hand /
close friend, familiar, intimate, crony, alter ego, bosom friend
"Disaster" is probably the closest synonym, but "distress" rather close.
compact, packed, close, compressed
close, terminate, climax, conclude
A close synonym is:deformed
Beside, near, close (to), in close proximity, about, encompassing, encircling, surrounding