v. an·ni·hi·lat·ed, an·ni·hi·lat·ing, an·ni·hi·lates
a. To destroy completely: The naval force was annihilated during the attack.
b. To reduce to nonexistence: "He had not just to hide his hunger; so as not to go mad he had to annihilate it" (Philip Roth).
c. To defeat decisively: annihilated the league champions in the playoffs.
2. Physics To convert (a subatomic particle) to energy or high-energy particles by annihilation.
1. To be completely destructive.
2. Physics To participate in annihilation. Used of particles and antiparticles.
[Late Latin annihilāre, annihilāt- : Latin ad-, ad- + Latin nihil, nothing; see ne in the Appendix of Indo-European roots.]
an·ni′hi·la·bili·ty (-lə-bĭlĭ-tē) n.
an·nihi·la·ble (-lə-bəl) adj.
Synonyms: annihilate, exterminate, extinguish, obliterate
These verbs mean to destroy completely. Annihilate often implies that the destruction is so severe that nothing is left or salvagable: The cannon blasts annihilated the enemy's fortifications.
Exterminate emphasizes the elimination of that which is considered undesirable, especially by killing: "The land had been rendered treeless, as though a tree were a parasite that needed to be exterminated, its stump uprooted and purged" (Madhusree Mukerjee).
Extinguish is to put an end to something or to make something extinct: The teacher's criticism of my essay extinguished my enthusiasm for the project.
To obliterate is to leave no trace of that which is destroyed: The virus obliterates all data on the hard drive of any computer it infects.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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.