machine burn: A darkening of wood due to overheating by a cutting edge. Due to a dull cutting edge or wood and cutting edge remaining in contact too long.

manufacturing defects: Includes all defects or blemishes that are produced in manufacturing, such as chipped grain, torn grain, skips in dressing, hit and miss ( a series of surfaced areas with skips between them) variation in machining, machine burn, mismatching.

mastic: The material used in a glue-down installation to adhere wood floors to approved interior subfloors.

MBF: Thousand board feet.

MDF Medium Density Fiberboard: A core or panel product manufactured from wood fibers combined with synthetic resin or other bonding system. MDF is manufactured with medium density of 331 lbs/cubic foot up to 55 lbs/cubic foot by the application of heat and pressure.

mechanical defects: Wood flaws caused by mechanical means most often a drying defect.

mechanical fastener: A mechanical device such as a cleat or staple or nail Specifically designed for the purpose of installing wood flooring. The fastener is coated(staples), or serrated (Nails/cleats) to increase holding power. The fastener is used typically within the pocke

medallion/inlay: A pattern located at a focal point of the floor

medullary rays: Strips of parenchyma cells that extend radially from the core of the tree toward the bark. Vary in height from a few cells in some species to four or more inches in oaks. Rays serve primarily to store food and transport it horizontally in the tree. Respon

metal stain: A dark gray or black stain that can be caused in some woods when they are moist and touching ferrous metal.

metamerism: An apparent change in color when exposed to different wavelengths of light, the human perception of color. The phenomenon by which colors of specimens match when illuminated by the light of one spectral composition despite differences in spectral reflecta

methyl ethyl ketone: MEK a low boiling point, highly volatile flammable solvent with extremely good solubility for most vinyls, urethanes and other coatings.

micro bevel: A small( less than 1mm) 45 degree bevel used on the edges of prefinished wood flooring.

Mil: One thousandth of an inch.


mildewcide: A chemical that inhibits the growth of mildew by killing the fungi that caused it.

milky: Having the appearance of milk or showing some whiteness, as when water is mixed with varnish or when dried transparent film starts to turn white from moisture.

mill run (run of the mill): Flooring that is milled from one grade of lumber, without being further separated by flooring grades.

milling defects: Blemishes produced in milling flooring such as chipped grain, torn grain, variations in milling, machine burns and mismatching.

millwork: Objects manufactured at a lumber mill or woodworking plant for use in the building construction industry- includes doors and windows and their trim, decorative interior trim, stairway components, fireplace mantels etc.(flooring not included).

mineral oil: A refined petroleum product with low volatility suitable for use as a wood finishing agent.

mineral spirits: A refined petroleum product with a high volatility suitable for some thinning operations. Paint thinner contains mineral spirits.

mineral stain: An olive to greenish-black or brown discoloration caused by regions of abnormal concentrations of mineral matter in some hardwoods. Minerals are brought up into the tree by the sap and stain occurs parallel to the pores.

mineral streak: Wood containing an accumulation of mineral matter introduced by sap flow, causing an unnatural color ranging from greenish brown to black.

mirrored polish finish: Requires several steps of wet sanding, mechanical buffing and polishing.

mitered corner: Corner pattern in which two perpendicular boards are joined by cutting the ends of each at an angle.

mixed media: A wood floor that also incorporates other materials such as slate, stone, ceramic tile, marble or metal.

moisture content: The weight of the water within a piece of lumber measured as a percentage of the weight of the oven dried weight of the wood. (weight of the water in the wood divided by the weight of the wood without any water) The amount of moisture in wood expressed a

moisture gradient: A progressive change (+ or -) in moisture content between the core and the surface of a piece of wood.

moisture meter: An electronic instrument for determining the moisture content of wood. There are two types of meter- one measures electrical resistance of the wood, the other measures the dielectric property of the wood.


mosaic parquet: A parquet floor made up of small solid pieces of wood ( slats) assembled as units that may consist of individual squares, units with slats arranged in single or double herringbone design or units or squares bordered with slats of the same or contrasting s

mottled: spots of different tones and colors placed next to one another to obtain blotchy or patch effects

moulder blank: A piece of lumber that has been planed and ripped to a size slightly larger than the finished size of the moulding to be run.

movement in service:

mud cracking: Paint film defect characterized by irregular broken network of cracks in the film.

muddy: lacking a bright, clear, transparent appearance, when speaking of clear materials. A muddy color is one having a trace of brown in it which takes away the purity or brightness of the color.