a separate and self-contained entity

of or pertaining to or involving the use of units

a portion of a natural object

separate or classify into units

make into a unit

divide (bulk material) and process as units

(chemistry) a series of linked atoms (generally in an organic molecule)

(physics) something joined by two equal and opposite forces that act along parallel lines

the smallest group of atoms or molecules whose repetition at regular intervals in three dimensions produces the lattices of a crystal

(chemistry) two or more atoms bound together as a single unit and forming part of a molecule

(physics and chemistry) the simplest structural unit of an element or compound

a portion of a natural object