What is the meaning of ob?

In some Words it means towards or against.eg object is to throw towards obverse is to turn towards obsequious is to follow towards

The prefix ob- means on or near, before, toward or against, as in offer; with a negative connotation as in occlude; opposite to or in front of as in obstetric; on account of; in a different direction, downward as in omit; away from as in obliterate; and it indicates intensified action as in obdurate.