Assumption and Supposition

Assumption

Assumption noun - Something taken as being true or factual and used as a starting point for a course of action or reasoning.
Usage example: your argument is faulty because it's based on erroneous assumptions

Supposition is a synonym for assumption in conjecture topic. In some cases you can use "Supposition" instead a noun "Assumption", when it comes to topics like anticipation, reason, hypothesis, presumption. popular alternative

Nearby Words: assume, assumed, assumptive

Supposition

Supposition noun - An idea that is the starting point for making a case or conducting an investigation.
Usage example: my supposition is that this grape variety, which flourishes in southern France, should do equally well here, given the similar climate

Assumption is a synonym for supposition in conjecture topic. You can use "Assumption" instead a noun "Supposition", if it concerns topics such as anticipation, belief, reason, guess. popular alternative

How words are described

rational rational assumption rational supposition
common common assumption common supposition
valid valid assumption valid supposition
unreasonable unreasonable assumption unreasonable supposition
Cite this Source
Supposition and Assumption. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/assumption/supposition
Assumption & Supposition. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/assumption/supposition>.
Supposition or Assumption. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/assumption/supposition.
Google Ngram Viewer shows how "assumption" and "supposition" have occurred on timeline