そうそう

  1. adjectival nouns or quasi-adjectives (keiyodoshi), adverb taking the 'to' particle, noun (common) (futsuumeishi)

    busy, hurried, rushed

  2. expressions (phrases, clauses, etc.)

    yours sincerely, yours in haste
    letters ending with this start with 前略, 冠省, etc.

  3. adjectival nouns or quasi-adjectives (keiyodoshi), noun (common) (futsuumeishi)

    simple, brief, quick
    archaic