Man pages matching name umount in section 8:

umount.8.de	debian 10 / manpages-de
umount.8.hu	debian 10 / manpages-hu
umount.8.ja	debian 10 / manpages-ja
umount.8.pl	debian 10 / manpages-pl
umount.8.tr	debian 10 / manpages-tr
umount.8.zh_CN	debian 10 / manpages-zh
umount.8.zh_TW	debian 10 / manpages-zh
umount.8.en	debian 10 / mount
umount.8.de	debian 11 / manpages-de
umount.8.fr	debian 11 / manpages-fr
umount.8.hu	debian 11 / manpages-hu
umount.8.ja	debian 11 / manpages-ja
umount.8.pl	debian 11 / manpages-pl
umount.8.tr	debian 11 / manpages-tr
umount.8.zh_CN	debian 11 / manpages-zh
umount.8.zh_TW	debian 11 / manpages-zh
umount.8.en	debian 11 / mount
umount.8.de	debian 12 / manpages-de
umount.8.fr	debian 12 / manpages-fr
umount.8.ja	debian 12 / manpages-ja
umount.8.pl	debian 12 / manpages-pl
umount.8.tr	debian 12 / manpages-tr
umount.8.uk	debian 12 / manpages-uk
umount.8.zh_CN	debian 12 / manpages-zh
umount.8.zh_TW	debian 12 / manpages-zh
umount.8.en	debian 12 / mount
umount.8.ja	debian 13 / manpages-ja
umount.8.tr	debian 13 / manpages-tr
umount.8.zh_CN	debian 13 / manpages-zh
umount.8.zh_TW	debian 13 / manpages-zh
umount.8.en	debian 13 / mount
umount.8.de	debian 13 / util-linux-locales
umount.8.pl	debian 13 / util-linux-locales
umount.8.ro	debian 13 / util-linux-locales
umount.8.uk	debian 13 / util-linux-locales
umount.8.sr	debian 13 / util-linux-locales