Expletive /(?)/

Ex·ple·tive

Expletive

a.
  1. Filling up; hence, added merely for the purpose of filling up; superfluous.
    Expletive phrases to plump his speech.

Expletive

n.
  1. A word, letter, or syllable not necessary to the sense, but inserted to fill a vacancy; an oath.
    While explectives their feeble aid to join, And ten low words oft creep in one dull line.