apropos - Locates reference pages by keyword
The apropos command shows which reference pages contain instances of any of
the given keywords in their purpose lines.
Specifies the word(s) for which apropos should search.
In looking for keywords, apropos considers each word separately and ignores
the case of letters. Words that are part of other words are also con-
sidered; thus, when looking for the word compile, apropos will also find
all instances of compiler.
If the output of the apropos command begins with a name and reference sec-
tion number, you can enter man section name. For example, if the output of
the apropos command is make(1u), you can enter man 1u make to obtain the
reference page on System V version of the make command.
The apropos command works just like the man command with the -k option.
To find reference pages with the keyword password in the purpose line,
Commands: man(1), whatis(1), catman(8)