noun, plural po·ros·i·ties for 2. the state or quality of being porous. Geology, Engineering. the ratio, expressed as a percentage, of the volume of the pores or interstices of a substance, as a rock or rock stratum, to the total volume of the mass.

What does porosity mean for hair?

You may have heard the term “hair porosity” and wondered what it means. Essentially, hair porosity is about your hair's ability to absorb and retain moisture. The porosity of your hair affects how well oils and moisture pass in and out of the outermost layer of your hair, known as the cuticle.

What is my porosity?

Another way to check your hair porosity is to drop hair that's been shed as a result of combing into a glass of water. If it floats, your hair is low porosity. If your hair sinks slowly, it has normal porosity, and if it sinks immediately, your hair is high porosity.