1. 1. in opposition to or competition with a fight against evil
   2. contrary to against one's will
2. toward so as to press on or strike push against the door; throw the ball against the wall
3. in contact with a ladder leaned against the barn
4. opposite to the course or direction of driving against the traffic
5. 1. in contrast with green against the gold
   2. in comparison with items checked against a list
6. in preparation for; for the possibility of we provided against a poor crop
7. as a debit or charge on a bill entered against our account
8. Now Dial. next to; adjoining the house against the church

Etymology: ME ayeynst, opposite to, facing < OE ongegn, ongean (see again), with adv. gen. -es + unhistoric -t

conjunction