When we encounter two or more words with the same form and related meanings, we have what is technically known as polysemy. Polysemy can be defined as one form (written or spoken) having multiple meanings that are all related by extension. Examples are the word head, used to refer to the object on top of your body, froth on top of a glass of beer, person at the top of a company or department, and many other things. Other examples of polysemy are foot (of person, of bed, of mountain) or run (person does, water does, colors do).

If we aren’t sure whether different uses of a single word are examples of homonymy or polysemy, we can check in a dictionary. If the word has multiple meanings (i.e. it’s polysemous), then there will be a single entry, with a numbered list of the different meanings of that word. If two words are treated as homonyms, they will typically have two separate entries. In most dictionaries, bank, mail, mole and sole are clearly treated as homonyms whereas face, foot, get, head and run are treated as examples of polysemy.

Of course, it is possible for two forms to be distinguished via homonymy and for one of the forms also to have various uses via polysemy. The words date (= a thing we can eat) and date (= a point in time) are homonyms. However, the “point in time” kind of date is polysemous in terms of a particular day and month (= on a letter), an arranged meeting time (= an appointment), a social meeting (= with someone we like), and even a person (= that person we like). So the question How was your date? could have several different interpretations.