a. (UN-1 7. Cf. Du. onzusterlijk, Sw. osysterlig.)
1742. Richardson, Clarissa (1811), I. 96. Your Bell’s unsisterly behaviour.
c. 1815. Jane Austen, Persuas., vi. Mary was not so repulsive and unsisterly as Elizabeth.
1860. W. S. Hayward, Beautiful Demon, 103. You wrong me, Regina. It is cruel, it is unsisterly of you.
