Not sure if you already got your answer on this, but the word “parse” has these synonyms: https://www.merriam-webster.com/thesaurus/parse
“Parse” is often used in a technical sense to refer to any code that takes an input and returns something. It has a different meaning than “functions” in that “parsing” usually has the subtext of scanning or analyzing its input, while “functions” have a broader meaning.
In the plainest English possible, parseInt takes an input string that looks like a number (but isn’t a number, as strings and numbers are different and aren’t necessarily interchangeable) and actually converts it to a number.
parseInt is often used when getting input from forms when reading in numbers that were originally entered as strings. Or to ensure validity that a string contains a number.