Answer: vastest

AnswerCrossword Clue
VASTESTMost expansive
VASTESTEncompassing the most space
VASTESTMost extensive
VASTESTMost immense.
VASTESTMost enormous.
VASTESTLargest in scope
VASTESTMost widespread
VASTESTLike Russia, of all countries
VASTESTMaximally massive
VASTESTMost immense
vastestimmense; huge
vastestVAST, of great extent or size