An Etymological Dictionary of Astronomy and Astrophysics

1. A suffix used in chemical terminology, in particular to indicate a salt of an acid ending in -ic and not beginning with → hydro-, such as silicate, nitrate, sulfate.
   

2. Verbal suffix denoting “to act upon” (in a specific way), “to cause to become.”

See also: 1) From M.E. -aten, from L. -atus p.p. ending of 1st conjugable verbs.

2. Very likely from N.L. expressions as plumbum acetatum salt produced by the action of acetic acid on lead.