Protection.
ETYM Old Eng. sheld, scheld, AS. scield, scild, sceld, scyld; akin to OS. scild, OFries. skeld, Dutch and German schild, Old High Germ. scilt, Icel. skjöldr, Swed. sköld, Dan. skiold, Goth. skildus; of uncertain origin. Related to Sheldrake.
In geology, alternate name for craton, the ancient core of a continent.
1. A protective structure or device (usually metal).
2. Armor carried on the arm to intercept blows; SYN. buckler.