'man ps' says "see also ... stime" but doesn't describe stime

'man ps' has several references to stime (as a possible argument to, say, -o), for example

       bsdstart START time the command started. If the process
                             was started less than 24 hours ago, the
                             output format is " HH:MM", else it is "
                             Mmm:SS" (where Mmm is the three letters of
                             the month). See also
                             lstart, start, start_time, and stime.

However, there is no entry for stime. (There's stime(2), but that's unrelated to ps, and anyway 'stime' here appears in a list with other things that do appear in the "standard format specifiers" section.)

$ lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04
$ apt-cache policy procps
procps:
  Installed: 1:3.3.9-1ubuntu2.2
  Candidate: 1:3.3.9-1ubuntu2.2
  Version table:
 *** 1:3.3.9-1ubuntu2.2 0
        500 http://us.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     1:3.3.9-1ubuntu2 0
        500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages