the.com/shield wall

means A defensive tactic where warriors stand shoulder to shoulder, overlapping their shields into a single unbroken barrier against the enemy.

from A plain compound of 'shield' and 'wall' — the word describes exactly what it is, no disguise needed. The tactic itself is ancient and widespread, used by Greek hoplites, Roman legions, and famously the Anglo-Saxons and Vikings, whose sagas and poems (the term appears in Old English as 'scildweall') gave the English word its lasting form. The name survived because the image needed no embellishment: men locking shields into a wall was already the whole poem.