be·troth (bĭ-trōth, -trôth)
tr.v. be·trothed, be·troth·ing, be·troths
To promise to give in marriage: was betrothed to a member of the royal family.
[Middle English bitrouthen : bi-, be- + trouth, troth (from Old English trēowth; see deru- in the Appendix of Indo-European roots).]
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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:
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.