Imporosity is a relatively rare word, with limited synonyms available to convey its exact meaning. However, there are some alternatives that could be used to replace or complement the word. For example, the words "permeability," "porosity," and "impermeability" are close in meaning. The term "breathability" could also be used in certain contexts where air or gases flowing through a material or substance is required. Additionally, the term "pores" could be used to refer to the openings or gaps through which substances can flow. Finally, the words "leakiness," and "absorbency" may also be appropriate depending on the context in which the word is used.