counter (n.) Look up counter at Dictionary.com
mid-14c., "table where a money lender does business," from O.Fr. contouer "counting room, table of a bank," from M.L. computatorium "place of accounts," from L. computare (see compute). Generalized 19c. from banks to shops, then extended to display cases for goods. Countertop is attested from 1878. Phrase under the counter is from 1926.
counter (v.) Look up counter at Dictionary.com
"go against," early 14c., from O.Fr. countre "facing opposite" (see counter-).