Make sure you're quoting the URL for the shell command:
wget
"https://en.wikipedia.org/w/api.php?action=parse&page=Aphrodisiac&prop=wikitext&format=json"
Otherwise characters such as '&' may be interpreted by the shell,
causing you to query the wrong URL.
If the page title contains quotes or other special characters, you will
also need to escape them, in a way that depends on your shell.
If you can, do this work from Python, it's a lot less error-prone.
--
Bartosz Dziewoński