fast 2 (făst)
intr.v. fast·ed, fast·ing, fasts
1. To abstain from food.
2. To eat very little or abstain from certain foods, especially as a religious discipline.
1. The act or practice of abstaining from or eating very little food.
2. A period of such abstention or self-denial.
[Middle English fasten, from Old English fæstan; 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.