To explode or otherwise destroy something into tiny, fragmentary pieces. Smithereens, first appearing in 1829 as "smiddereens," is likely derived from the Irish word "smidirín" or "smidiríní," meaning fragment. The demolition crew came in and blasted the house to smithereens.The small band of rebels didn't stand a chance; they were blasted to smithereens as soon as the loyalists had them in sight.