1. (prep.) Abreast; opposite to; facing; towards; as, against the mouth of a river; -- in this sense often preceded by over.

2. (prep.) From an opposite direction so as to strike or come in contact with; in contact with; upon; as, hail beats against the roof.

3. (prep.) In opposition to, whether the opposition is of sentiment or of action; on the other side; counter to; in contrariety to; hence, adverse to; as, against reason; against law; to run a race against time.

4. (prep.) By of before the time that; in preparation for; so as to be ready for the time when.

about across adverse to as to at cross-purposes with athwart con concerning confronting contra contrary to counter to dead against despite en route to facing for fronting headed for in conflict with in contact with in contempt of in defiance of in disagreement with in front of in opposition to in order to in passage to in preparation for in spite of in transit to next to on on route to opposed to opposite opposite to over against re regardless of respecting to touching toward towards up up against upon versus vis-a-vis with respect to