on·slaught (ŏnslôt′, ôn-)
1. A violent attack.
2. An overwhelming outpouring: an onslaught of third-class mail.
[Alteration (influenced by obsolete slaughte, slaughter) of Dutch aanslag, a striking at, from Middle Dutch aenslach : aen-, on; see an- in the Appendix of Indo-European roots + slach, a striking.]
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Indo-European & Semitic Roots Appendicies
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.