A board foot is one foot long, one foot wide and one inch in thickness. Checking the Waste Mary Huston Gregory This is usually expressed in pounds per thousand board feet, a board foot being considered as one-twelfth of a cubic foot.
Sibilance is a manner of articulation of fricative and affricate consonants, made by directing a stream of air with the tongue towards the sharp edge of the teeth, which are held close together; a consonant that uses sibilance may be called a sibilant, or a strident.
Loudness is the characteristic of a sound that is primarily a psychological correlate of physical strength (amplitude). More formally, it is defined as that attribute of auditory sensation in terms of which sounds can be ordered on a scale extending from quiet to loud.