κρύφ-α^ [υ^], Adv., (κρύπτω)
A. = κρύβδα, without the knowledge of, c. gen., Th.1.101.
2. abs., secretly, Aen.Tact.2.4; by ballot, Th. 4.88; obscurely, “κ. καὶ δι᾽ αἰνιγμάτων” Plu.2.1125e.
What does "abs." mean here? I have a guess, but I'm curious to first hear what others have to say.
Thanks in advance.