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Webster 1913 Edition
Thummim
Thum′mim
,Noun.
 pl.
 [Heb., pl. of 
thōm 
perfection.] A mysterious part or decoration of the breastplate of the Jewish high priest. See the note under 
Urim
. Webster 1828 Edition
Thummim
THUM'MIM
,Noun.
 plu.