From MarineBiotech Infopages
Definition of organotin compounds:
Compound that contains both tin and carbon. 
This is the common definition for organotin compounds, other definitions can be discussed in the article
The most common organotin compounds are tributyltin (TBT) and its degradation products dibutyltin (BBT) and butyltin. TBT is the most hazardous organotin and has been widely used in antifouling paints.