The crossword solution for the term 'dialect anagram' is 'CITADEL'. A CITADEL is a fortress or stronghold, typically located in a city. It is usually used as a defensive structure and is often the last line of defense against an enemy. The term can also refer to any strong or secure place, such as a castle or a fortified town. In this context, it could be used to describe a dialect that is strongly defended and resistant to change.