HEBREW / ARAMAIC · H8550
תֻּמִּים
tum.mim — Thummim
§ Thummim = "perfection" 1) stones provided for the means of achieving a sacred lot 1a) used with the Urim, the will of God was revealed
5 tagged verse occurrences · see every occurrence →BIBLE DICTIONARY + WORD STUDY
How to read this: there is rarely one magic “true meaning” hidden behind an English word. A lexicon records a word’s semantic range. The intended meaning is narrowed by grammar, sentence, author, historical usage and context.
HEBREW / ARAMAIC · H8550
tum.mim — Thummim
§ Thummim = "perfection" 1) stones provided for the means of achieving a sacred lot 1a) used with the Urim, the will of God was revealed
5 tagged verse occurrences · see every occurrence →HEBREW / ARAMAIC · H2833
cho.shen — breastpiece
1) breastplate, breastpiece 1a) sacred pouch of the high priest designed to hold the Urim and Thummim
21 tagged verse occurrences · see every occurrence →Perfection (LXX., “truth;” Vulg., “veritas”), Ex. 28:30; Deut. 33:8; Judg. 1:1; 20:18; 1 Sam. 14:3, 18; 23:9; 2 Sam. 21:1. What the “Urim and Thummim” were cannot be determined with any certainty. All we certainly know is that they were a certain divinely-given means by which God imparted, through the high priest, direction and counsel to Israel when these were needed. The method by which this was done can be only a matter of mere conjecture. They were apparently material objects, quite distinct from the breastplate, but something added to it after all the stones had been set in it, something in addition to the breastplate and its jewels. They may have been, as some suppose, two small images, like the teraphim (comp. Judg. 17:5; 18:14, 17, 20; Hos. 3:4), which were kept in the bag of the breastplate, by which, in some unknown way, the high priest could give forth his divinely imparted decision when consulted. They were probably lost at the destruction of the temple by Nebuchadnezzar. They were never seen after the return from captivity.
Source: Easton’s Bible Dictionary (1897). Historical dictionary wording reflects the scholarship and language of its era.