is a specific kind of: covering.

is a broader term that covers: armor, armour | bell glass, bell jar | binder, ring-binder | back, binding, book binding, cover | blind, screen | armguard, bracer | cap | cloche | coaster | cold frame | crystal, watch crystal, watch glass | dust cover | faceplate | cladding, facing | fall-board, fallboard | escutcheon, finger plate, scutcheon | heat shield | bonnet, cowl, cowling, hood | housing | lamp shade, lampshade, shade | liner, lining | mask | mulch | roof | roof | screen | shade | sheath | overlay, overlayer, sheathing | shelter | shield | dashboard, splashboard, splasher | splasher | testudo | thumbstall | toecap | splashboard, washboard ... show more.

derivation: protect.