Concrete Canoe. The Greek polymath Archimedes is said to have solved the mystery of buoyancy in a bathtub. Even if the story is apocryphal, his principle isn't: If an object weighs less than the water it displaces, it won't sink. Even concrete can float. Materials scientist Joseph-Louis Lambot built a concrete dinghy featured in the 1855 World's Fair.
Definition of BIOFILTER. : a filter bed in which sewage is subjected to the action of microorganisms that assist in decomposing it. ADVERTISEMENT. 2bi- + filter.rigin of BIOFILTER. 2bi- + filter. This word doesn't usually appear in our free dictionary, but the definition from our premium Unabridged Dictionary is offered here on a limited basis.
Falter (verb) to thrash in the chaff; also, to cleanse or sift, as barley. Falter. to hesitate; to speak brokenly or weakly; to stammer; as, his tongue falters. Falter. to tremble; to totter; to be unsteady. Falter. to hesitate in purpose or action. Falter. to fail in distinctness or regularity of exercise; -- said of the mind or of thought. Falter (verb) to utter with hesitation, or in a broken, trembling, or weak manner. Falter (verb) hesitation; trembling; feebleness; an uncertain or broken sound; as, a slight falter in her voice. Origin: [See Falter, v. i.]