Sentence:  Upon consideration of the variety of soils and fabrics normally encountered in the washing process , it is little wonder that the use of a number of detergent constituents having `` <WSD>synergistic</WSD> '' properties has gained widespread acceptance . 
Meaning of the word marked with <WSD> tags:  used especially of drugs or muscles that work together so the total effect is greater than the sum of the two (or more)