hush-hush

hush-hush  {adj.},  {informal}
Kept secret or hidden; kept from public knowledge; hushed up; concealed.
The company had a new automobile engine that it was developing, but kept it a hush-hush project until they knew it was successful.
Categories: adjective cars informal

An client error occurred: Error calling GET https://www.googleapis.com/youtube/v3/search?part=id%2Csnippet&q=%22hush-hush%22&maxResults=4&videoEmbeddable=true&videoSyndicated=true&safeSearch=strict&type=video&key=AIzaSyCfLRuAZZNAQm6a5uDzgY-Tt668bxsppCs: (403) The request cannot be completed because you have exceeded your <a href="/youtube/v3/getting-started#quota">quota</a>.