Translations:Knowledge Base:Accepting a keyword for a single package/1/en
From Gentoo Wiki
Not all software present in the Gentoo repository will be immediately available to install with the emerge command. Software that is still undergoing testing (also referred to as stabilization) is hidden by a keyword and needs to be explicitly accepted in order to be installed (except when using the testing branch system-wide). Beware that using software from the testing branch might incur stability issues, it is not recommended for inexperienced users.