Noun
oxoanion (plural oxoanions)
(chemistry) Any anion derived from an oxoacid
Basic (ortho-)silicate oxoanion ( SiOmain ) structure A silicate is a compound containing an anionic silicon compound. Source: Internet
Consider the chlorine oxoanion family: First, think of the -ate ion as being the "base" name, in which case the addition of a per- prefix adds an oxygen. Source: Internet