Fungus - Fungus is singular for one type of a plant-type organism such as a mold or a mildew.

Fungi - Fungi or funguses is plural for multiple types of fungus.

Fungicide - An antimicrobial used to kill molds and mildews. They consist of many different types but bleach is the most commonly used in the home.

Fungistat - An antimicrobial used to prevent mold or mildew from growing provided it hasn't already colonized.

HEPA - (hee pa) HEPA stands for High Efficiency Particulate Air. I believe HEPA should stand for Highly Efficient Particulate Arrester. Meaning it stops the particle by trapping it in the filter, and high efficient air is the byproduct. A filter that removes 99.97 to 99.99 percent of airborne particles as small as 0.3 microns in diameter. They were invented by the Government in the nineteen fifty's to filter out nuclear active particles out of the air in nuclear power plants.

Hypha - (hi fa) Hypha is singular. Hypha is a single elongated, cylindrical, rod-shape filamentous (hair-like) microscopic plant organism forming the basic fungus structure.

Hyphae - (hi fay) Hyphae is plural for more then one filamentous fungi unit. In other words it's more then one plant-like organism.

Hypoallergenic - Someone who is easily stimulated by allergy causing materials.

Indirect Growth - Mold growth not associated with direct water such as a broken pipe or leaky roof. In other words growth that grows with high levels of humidity.

Industrial Hygienist - A professional qualified by education, training and experience to anticipate, recognize, evaluate and develop controls for occupational health hazards and environmental issues.

Immunocompromised - Someone who is unable to produce an adequate immune response to invasion by various pathogens, due to age, sickness, exhaustion or a regimen of drugs, any of which may render the body's immune system less than effective.

Mycelia - Advanced colonies of mycelia is just another way of saying a group of fungus. A large number of individual units clumped together making it visible to the naked eye.

Permeate - To migrate through. Water that evaporates out of porous or semi-porous materials.

Spore - A walled, single-to-many-celled reproductive body of an organism, capable of giving rise to a new individual either directly or indirectly. A reproductive seed-like element that detaches from fungi and is a sexual reproductive element. Also see conidium. In other words its a seed from fungus.

Yeasts - Yeasts are unicellular fungi. In other words molds are formed by long chains of cells, yeasts are separate microscopic plant-like organisms.