Invalid and Weak

Invalid

Invalid adjective - Chronically or repeatedly suffering from poor health.
Usage example: an old and now invalid woman who rarely gets out anymore

Weak is a synonym for invalid in feeling topic. In some cases you can use "Weak" instead an adjective "Invalid", when it comes to topics like sickly, false, disabled.

Weak

Weak adjective - Lacking bodily strength.
Usage example: the little boy was simply too weak to lift the box

Invalid is a synonym for weak in deficient topic. You can use "Invalid" instead an adjective "Weak".

Both words in one sentence

  • Indeed monarchists often note that revolutions only happen against weak rulers (Charles I, Louis XVI, Nicholas II) rather than strong rulers, which means that The Kingdom as a system is not invalid except for the weak rulers who potentially come to power.
Cite this Source
Weak and Invalid. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/invalid/weak
Invalid & Weak. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/invalid/weak>.
Weak or Invalid. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/invalid/weak.
Google Ngram Viewer shows how "invalid" and "weak" have occurred on timeline