Traditional practices of a society, or the government department that regulates imports and exports at borders.
From Old French 'costume', from Latin 'consuetudo' meaning 'habit' or 'usage'. The border control meaning developed because import duties were based on 'customary' practices and rates established by tradition.
The phrase 'customer' actually comes from the same root as 'customs' - originally, a customer was someone who customarily bought from a particular merchant. Modern customs agencies evolved from medieval toll collectors who charged fees based on local customs and traditions.
Complete word intelligence in one call. Free tier — 50 lookups/day.