- An unfertilized, rounded mass of protoplasm, produced in
an oogonium. - An analogous mass of protoplasm in the ovule of a
flowering plant; an embryonic vesicle.
- Impenetrable - Invincible - Invulnerable - Not to be overthrown - Unassailable - Not to be stormed, or taken by assault; incapable of
being subdued; able to resist attack; unconquerable; as, an impregnable
fortress; impregnable virtue. - Capable of being impregnated, as the egg of an animal,
or the ovule of a plant.
- The series of cells formed in the ovule of a flowering
plant after fertilization, but before the formation of the embryo. - The primary growth from the spore in certain
cryptogamous plants; as, the proembryo, or protonema, of mosses.