Synonyms for the phrase "renders invalid" are abundant and come in various forms depending on the context. Some common synonyms include nullify, negate, invalidate, void, annul, abolish, revoke, and repeal. These words share a common meaning of canceling or making ineffective something that was previously considered valid or binding. When describing legal or contractual agreements, terms like rescind, terminate, or abrogate may also be used. In technical or scientific contexts, words like disqualify, deface, or obsolesce may be more appropriate. Depending on the tone and intent of the conversation, it's important to choose the right synonym to accurately convey the message without being too extreme or offensive.