Definition of "vexatious"

vexatious

/vɛkˈseɪʃəs/

adjective
comparative more vexatious, superlative most vexatious
1. Causing vexation or annoyance; teasing; troublesome.
  Quotations
  Although this letter is vexatious, I must not forget that my little entertainment has brought me a visiter in the Marquess of Wentworthdale, on an errand of no small moment, as the Countess of Rotheles may soon learn, to her surprise, for I shall, probably, see him at the Opera to-night.
  1838 (date written), L[etitia] E[lizabeth] L[andon], chapter XXI, in Lady Anne Granard; or, Keeping up Appearances. […], volume I, London: Henry Colburn, […], published 1842, page 259
2. (archaic) Full of trouble or disquiet
  Quotations
  He leads a vexatious life.
  1644, Kenelm Digby, Two Treatises, To My Son Kenelm Digby (preface)
3. (law, of an action) Commenced for the purpose of giving trouble, without due cause.
4. (law, of a party or entity) In the habit of starting vexatious litigation and therefore liable to have restraints placed on one's ability to access the courts.