“Spray adjuvant” means any wetting agent, spreading agent, deposit builder, adhesive, emulsifying agent, deflocculating agent, water modifier, or similar agent, with or without toxic properties of its own, which is intended to be used with another pesticide as an aid to the application or effect of the other pesticide, and sold in a package that is separate from that of the pesticide other than a spray adjuvant with which it is to be used.