Real Dictionary

detour
countable noun: A detour is a special route for traffic to follow when the normal route is blocked, for example because it is being repaired.
countable noun: If you make a detour on a journey, you go by a route which is not the shortest way, because you want to avoid something such as a traffic jam, or because there is something you want to do on the way.

detour in American English
a roundabout way; deviation from a direct way
to cause to go by way of a detour
to go by way of a detour
intransitive verb: to make a detour; go by way of a detour
noun: a roundabout or circuitous way or course, esp. one used temporarily when the main route is closed
transitive verb: to cause to make a detour

detour in British English
noun: a deviation from a direct, usually shorter route or course of action
verb: to deviate or cause to deviate from a direct route or course of action