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Webster 1913 Edition

Adj.

Furnished with a bastion; having bastions.

bastioned ‎(not comparable)

Furnished with a bastion; having bastions.
- 1919, Achmed Abdullah, "Pro Patria" in Fear and Other Stories, Chapter IV,
  As he walked stiffly aslant against the booming northern wind, he tried to marshal his thoughts, tried to dovetail for himself a picture of what had happened behind the grim, bastioned walls of the lamasery and of what was going to happen […]
- 1953, C. S. Lewis, The Silver Chair, Collins, 1998, Chapter 5,
  To the North there were low pale-colored hills, in places bastioned with rock.