neutralize

American Heritage® Dictionary of the English Language, Fourth Edition

1. v. To make neutral.
2. v. To counterbalance or counteract the effect of; render ineffective.
3. v. To declare neutral and therefore inviolable during a war.
4. v. Chemistry To make (a solution) neutral.
5. v. Chemistry To cause (an acid or base) to undergo neutralization.
6. v. Medicine To counteract the effect of (a drug or toxin).
7. v. Slang To remove as a threat, especially by killing.

Century Dictionary and Cyclopedia

1. To render neutral; reduce to a state of neutrality between different parties Or opinions. Specifically— To bestow by convention a neutral character upon (states, persons, and things Which would or might otherwise bear a belligerent character); declare non-belligerent, To prohibit hostilities within the limits of, as territory or waters.
2. In chem., to destroy or render inert or imperceptible the peculiar properties of, by chemical combination. See neutralization, 1.
3. To render inoperative; invalidate; nullify; counterbalance: as, to neutralize opposition.
4. Also spelled neutralise. Synonyms Annul, Nullify, Annihilate, Neutralize. These words agree in meaning the bringing of a thing to nothing, causing it to cense to be absolutely, or us to some special relation. Annul represents an official or authoritative act: as, to annul an edict. (See abolish.) Nullify, to render invalid or of no avail, is more general and less often official: a law may be illegally nullified by inert resistance. To annihilate is to reduce to nothing, and should be used only where absolute putting out of existence is meant; such expressions as “his army was literally annihilated” are manifestly improper; “his army was annihilated” would be proper by strong hyperbole, if the army was so broken up that no parts of it were ever gathered together again. To neutralize is to bring to nothing in respect to some special relation, or to render inoperative or inefficacious in respect to certain other agencies or forces, by a contrary or counter balancing force: as, to neutralize an acid; his efforts were neutralized by the influence of his opponent. That which is neutralized would naturally have force in itself; hence we should not speak of neutralizing a law or a command.
5. In motor-racing, to give a neutral character to (a town or to a specified part of a road), that is, to arrange that the time used in passing through or over it is not to be counted in the race.

Wiktionary

1. v. American alternative spelling of neutralise.

GNU Webster's 1913

1. v. To render neutral; to reduce to a state of neutrality.
2. v. (Chem.) To render inert or imperceptible the peculiar affinities of, as a chemical substance; to destroy the effect of.
3. v. To destroy the peculiar properties or opposite dispositions of; to reduce to a state of indifference or inefficiency; to counteract; to render ineffective

WordNet 3.0

1. v. get rid of (someone who may be a threat) by killing
2. v. make politically neutral and thus inoffensive
3. v. make chemically neutral
4. v. make incapable of military action
5. v. make ineffective by counterbalancing the effect of
6. v. oppose and mitigate the effects of by contrary actions