1. Surgical excision or amputation of a body part or tissue.
2. The erosive processes by which a glacier is reduced.
a. The dissipation of heat generated by atmospheric friction, especially in the atmospheric reentry of a spacecraft or missile, by means of a melting heat shield.
b. The reduction or removal of heat-protective surface material by aerodynamic friction, as from a heat shield.
[Late Latin ablātiō, ablātiōn-, from Latin ablātus, past participle of auferre, to carry away : ab-, away; see AB-1 + lātus, carried; see telə- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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.