From Longman Dictionary of Contemporary Englishfirewallfire‧wall /ˈfaɪəwɔːl $ ˈfaɪrwɒːl/ noun [countable] 1 a special wall that prevents fires from spreading to other parts of a building2 a system that protects a computer network from being used or looked at by people who do not have permission to do so3 a system that is used by large financial or law companies to stop secret information from being passed from one department to another
Examples from the Corpus
firewall• A firewall is an embodiment of this security policy.• For example, a complete firewall product may cost anywhere between $ 0 to $ 200,000.• Implementing a high-end firewall from scratch might cost several man-months of effort.• They allow browser programmers to ignore the complex networking code necessary to support every firewall protocol and concentrate on important client issues.• Academic bodies tend not to have firewalls.• Some firewalls place a greater emphasis on blocking traffic, and others emphasize permitting traffic.• They set up private chat rooms on the internet with firewalls to prevent police hackers.From Longman Business Dictionaryfirewallfire‧wall /ˈfaɪəwɔːlˈfaɪrwɒːl/ noun [countable]1COMPUTING a system that protects a computer network from being used or looked at by people who do not have permission to do soBritish Aerospace uses a firewall so that individuals cannot be looked up in the directory of users.2FINANCELAWa system which is used by large financial and law companies to stop sensitive or confidential information being passed from one department to anotherSYNCHINESE WALLIt is in the interests of the universal bank to put in effect internal precautions such as firewalls. 