outbreeding n - The breeding of distantly related or unrelated individuals, often producing a hybrid of superior quality
ovary n - The ovule-bearing lower part of a pistil that ripens into a fruit
over-fertilization n - plant disease, characterized by slowed or stunted growth, wilting, chlorosis, and necrosis of the foliage, caused by toxification of the growing medium, due to an overabundance of chemicals
over-watering n - plant disease resulting from excessive moisture in the growing medium around the roots; characterized by root rot, damp rot, wilting, and slow or stunted growth
ovule n - A minute structure in seed plants, containing the embryo sac and surrounded by the nucleus, that develops into a seed after fertilization
oxygen (0 ) n - a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 28 percent of the atmosphere by volume; the most abundant element in the earth's crust; essential for plant and respiration; Atomic number 8; atomic weight 15.9994; melting point -218.4°C; boiling point -183.0°C; gas density at 0°C 1.429 grams per liter; valence 2.
ozonator or ozone generator n - device that produces ozone (O3) to purify the air and neutralize odor | 
