\Hal"i*dom\, n. [AS. h[=a]ligd?m holiness, sacrament,
sanctuary, relics; h[=a]lig holy + -d?m, E. -dom. See
{Holy}.]
1. Holiness; sanctity; sacred oath; sacred things; sanctuary;
   -- used chiefly in oaths. [Archaic]

         So God me help and halidom.           --Piers
                                               Plowman.

         By my halidom, I was fast asleep.     --Shak.

2. Holy doom; the Last Day. [R.] --Shipley.