ˈsisterliness [f. next + -ness.] The quality of being sisterly; sisterly affection or sympathy. 1879G. Meredith Egoist II. xi. 232 An elegant sisterliness, one might almost say.1882–3Advance (Chicago) 9 Aug., If you could experience once the brotherliness and sisterliness that warms our Annual [mission] Meetings.