Oxalis, n. From a Greek word meaning “acid”; a well-known plant, one form of which is called “wood sorrel.” It is called oxalis because of its acid juice.
Oxygen, n. One of the gases that compose the air and which is essential to life. It is also found in composition in the tissues of plants and animals.
P.
Pelargonium, n. From a Greek word meaning “a stork”; a member of the Geranium Family, so called because of the beaked seed-pods.
Petal, n. From a Greek word meaning “a leaf”; one of the leaves of a corolla.
Phosphorus, n. From a Greek word meaning “Lucifer, the morning star”; a solid substance which is luminous in the dark. It is found in composition in the bodies of animals and plants.
Pioneer, n. L. pes, a foot; in military terms, one of a company of foot soldiers who march before an army with implements to clear the way. Hence, whoever or whatever leads or prepares the way for others coming after.
Pistil, n. L. pistillum, a pestle; the seed-bearing organ of a flower, composed generally of three parts, ovary, style, and stigma, and called pistil because of its shape, which often resembles a pestle.
Plant cells, n. The cells of which plants are built up.
Pollen, n. L. pollen, fine flour; the dust or grains of fertilizing material found in the anthers of flowers.