Any heritable attribute of organisms that varies among terminal taxa, and so is useful for phylogenetic reconstruction.

Some attribute of individuals within a species for which various heritable differences can be defined.

A variable or characteristic measured or observed for a block of taxa. It could be from molecular data ("Nucleotide at position 367 of the 18S gene"), or it could be phenotypic ("length of wing"). Characters in Mesquite typically exist only within character matrices.

A heritable feature (e.g. tooth shape or DNA sequence) of a group of organisms that exists in multiple forms.

an attribute of an organism (contrast with Character state).

In animation, a model that uses special attributes such as skeleton joints and IK for animation. These attributes are set up and animated together, making it possible to create the complex mechanics required by characters.

In phylogenetics, characters are homologous features in different organisms. The exact condition of that feature in a particular individual is the character state.