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trans·il·lu·mi·na·tion

(trăns′ĭ-l′mə-nāshən, trănz′-)

The passing of a light through the walls of a body part or organ to facilitate medical inspection.

trans′il·lumi·nate′ (-lmə-nāt′) v.

trans′il·lumi·na′tor n.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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