stead·fast also sted·fast (stĕdfăst′, -fəst)
1. Firmly loyal or constant; unswerving. See Synonyms at faithful.
2. Fixed or unchanging: "my steadfast rule of not repeating anything in dance that I've done before" (Fred Astaire).
3. Fixed or unmovable: steadfast boulders in the stream.
[Middle English stedefast, from Old English stedefæst : stede, place; see STEAD + fæst, fixed, fast; see past- 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.