# A word for an informed guess in mathematics, proved later to be the correct guess

I am looking for a single word, used in mathematics (but not exclusively), meaning to take a guess which will later be proved to be correct.

I believe it starts with an 'a', and I seem to remember it being something similar to alcantz, alcats, ancaltz, first hearing it used by a professor in a lecture.

Edit (to add an example sentence): An example sentence: "I solved the problem through the use of an (insert word)."

• Hi packetpacket, welcome to EL&U. You might not be aware that there are strict rules for single-word-requests: "To ensure your question is not closed as off-topic, please be specific about the intended use of the word. You must include a sample sentence demonstrating how the word would be used." You can add this using the edit link. For further guidance, see How to Ask, and make sure you also take the EL&U Tour :-) – Chappo Feb 24 at 22:37
• I believe you're describing a hypothesis. Or a conjecture. Or a theorem. – michael.hor257k Feb 24 at 22:54

• Can we still use ansatz before we've verified it or if it turns out to be incorrect? e.g., I tried the anstatz $y=x^2$ but it did not work, or we are trying the ansatz $t=\cos u$ but we haven't verified it yet. – innisfree Feb 25 at 3:45