(uniq invocation, squeezing, The uniq command):

(uniq invocation, squeezing, The uniq command):
Use "repeated" rather than "duplicate" to describe adjacent
duplicates; this simplifies the description and makes it more
consistent with POSIX.
(uniq invocation): Make it clear that -d and -u suppress the
output of lines, rather than cause some lines to be output.
Mention what happens if a line lacks enough fields or characters.