An amount of substance of a system which contains as many elementary units as there are atoms of carbon in 0.012 kilogram of the pure nuclide carbon-12; the elementary unit must be specified and may be an atom, molecule, ion, electron, photon, or even a specified group of such units. Symbolized mol.

A breakwater or berthing facility, extending from shore to deep water, with a core of stone or earth.

A mechanical tunnel excavator.

1. A mass formed in the uterus by the maldevelopment of all or part of the embryo or of the placenta and membranes.

2. A fleshy, pigmented nevus.

Any of 19 species of insectivorous mammals composing the family Talpidae; the body is stout and cylindrical, with a short neck, small or vestigial eyes and ears, a long naked muzzle, and forelimbs adapted for digging.