APA Dictionary of Psychology

n. any ordered arrangement of data, particularly a two-dimensional grouping of data into rows and columns. The following listing of students’ scores on a test is an example of a simple array:

\begin{matrix} \mathrm{Student \; A} && 55\\ \mathrm{Student \; B} && 76\\ \mathrm{Student \; C} && 81\\ \mathrm{Student \; D} && 82\\ \mathrm{Student \; E} && 89\\ \mathrm{Student \; F} && 90\\ \mathrm{Student \; G} && 90\\ \mathrm{Student \; H} && 90\\ \mathrm{Student \; I} && 94\\ \mathrm{Student \; J} && 98\\ \end{matrix}
The concept may be extended to more than two dimensions.