(among the ancient Romans) a movable shelter with a strong and usually fireproof arched roof, used for protection of soldiers in siege operations.
2.
a shelter formed by overlapping oblong shields, held by soldiers above their heads.
Origin
1350-1400 for earlier sense “tumor”; 1600-10for def 1;Middle English < Latintestūdō tortoise, tortoise shell, siege engine; akin to test2
British Dictionary definitions for testudo
testudo
/tɛˈstjuːdəʊ/
noun (pl) -dines (-dɪˌniːz)
1.
a form of shelter used by the ancient Roman Army for protection against attack from above, consisting either of a mobile arched structure or of overlapping shields held by the soldiers over their heads