One word one almost never hears or reads these days is a very useful adjective meaning ‘superfluous’ and kindred senses. Here is how the OED Online defines it (preceded by its etymology):

Etymology: < classical Latin ōtiōsus ineffectual, superfluous, at leisure, unemployed, idle, inactive < ōtium otium n. + -ōsus ose suffix. Compare French oiseux (see otious adj.), Italian ozioso , †ocioso , †otioso (13th cent.), Old Occitan ocios (14th cent.), Spanish ocioso (1438).

  1. Of belief, principle, thought, etc.: having no practical result; unfruitful, sterile; futile, pointless. Having no practical function; redundant; superfluous.
  2.  At leisure; at rest; idle; inactive; indolent, lazy.
  3. How many times have we thought that something  was “superfluous” but had no other word to define this idea? Now we have “otiose,” which fits so may contemporary situations, n’est-ce pas?