From Longman Dictionary of Contemporary Englishtrunk roadˈtrunk road noun [countable] British EnglishTTR a main road used for travelling long distances
Examples from the Corpus
trunk road• The school is situated half way between Maidstone and Ashford on the A20 trunk road.• By 1676 it was part of the main Oxford to Coventry road and of course remains as a major trunk road today.• Some 40 new ones will be opened by 1995 on trunk road alone. 