characteristic of or meant for a single person or thing
being or characteristic of a single thing or person
a human being
separate and distinct from others of the same kind
concerning one person exclusively
a single organism
a set that is closed, associative, has an identity element and every element has an inverse
form a group or group together
any number of entities (members) considered as a unit
(chemistry) two or more atoms bound together as a single unit and forming part of a molecule
arrange into a group or groups