If your behavior or manner is altruistic, you show you care more about other people and their interests than you care about yourself.
If you adulterate something, you lessen its quality by adding inferior ingredients or elements to it.
An altercation is a noisy disagreement or heated argument.
An alteration is a change or modification to something.
An alternative to something is an other or different choice that is offered in addition to one you already have.
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