In minerology? and geology, it refers to a rock or ore containing phosphate ions.
In ecological terms, phosphate is often a [limiting reagent]? in many environments--the availability of phosphate governs the rate of growth of many organisms. Introduction of non-naturally occuring levels of phosphate to those environments causes an ecological disequilibrium, leading to booms in the population of some organisms and subsequent busts in the populations of others deprived of other nutrients or essential elements by the rapid growth and consumption by the booming population.
Phosphates are a component of certain types of detergent?, but because of boom-bust cycles tied to emission of phosphates into watersheds, phosphate detergent sale or useage is restricted in some areas.