This is the 1985th most frequent Polish word.
dowód
Proof; evidence; document.
In this sentence, "dowód" means proof or evidence, used to indicate justification of a statement.
To jest dowód na to, że mówiłem prawdę.
This is proof that I was telling the truth.
Here, "dowód" refers to an identity document, often a form of legal identification such as an ID card.
Na egzaminie musiałem przedstawić dowód tożsamości.
During the exam, I had to present an identity document.
In this case, "dowód" denotes a formal demonstration or logical verification in mathematics.