As the title asks, is it possible to install only the man page for a package - without installing the package itself? If so - what apt options are needed to make this happen?
I've reviewed man apt, man apt-get, man apt-preferences & done a brief online search. I didn't find anything that addressed this specific question.
This search result came closest. Running apt-cache search manpages revealed a few selected manuals, but not, for example, how to get the manpage for watchdog.
This answer turned up in a slightly different search. The link provided in the answer is apparently an obsolete page now. However, the following yielded a result that may answer the question:
$ apt-cache search debman
debian-goodies - Small toolbox-style utilities for Debian systems
$ sudo apt-get install debian-goodies
So far, so good... man debman exists (as does debman -h), but not very clear IMHO. Nevertheless, this seems to have gotten the job done:
$ debman -p watchdog watchdog
Get:1 http://mirror.sjc02.svwh.net/raspbian/raspbian buster/main armhf watchdog armhf 5.15-2 [82.5 kB]
Fetched 82.5 kB in 1s (102 kB/s)
Followed by man watchdog :
WATCHDOG(8) System Manager's Manual WATCHDOG(8)
NAME
watchdog - a software watchdog daemonSYNOPSIS
watchdog [-F|--foreground] [-f|--force] [-c filename|--config-file filename] [-v|--verbose] [-s|--sync] [-b|--softboot] [-q|--no-ac‐ tion]