They mean mA -- current in milli-Amperes.
wiki on Ampere
Ampere-hours is used as a capacity number for batteries (can provide that many amperes for one hour, 1/2 that current for two hours etc.).
Since current = charge / time [Ampere = Coulomb/s], current * time = charge [A* sec = coulomb].
Ah is an electric charge!
1 Ah = 3600 Coulomb. 1 mAh = 3.6 Coulomb. Cause 1 hour = 3600 sec.