ohassairi wrote:
in routers we can use the "ip host " command to map name to IP.
is there an equivalent command for firewalls?

You can use the "name" command which allows you to associate a name with an IP in the config -

http://www.cisco.com/en/US/docs/security/asa/asa72/command/reference/no_72.html#wp1652055

note that this is nothing to do with DNS mappings, it is just a handy way to have meaningful names in your config.

Jon