(usually plural) a necessary commodity for which demand is constant
a popular programming language that is relatively easy to learn; an acronym for beginner's all-purpose symbolic instruction code; no longer in general use
of or denoting or of the nature of or containing a base
serving as a base or starting point; "a basic course in Russian"; "basic training for raw recruits"; "a set of basic tools"; "an introductory art course"
pertaining to or constituting a base or basis; "a basic fact"; "the basic ingredients"; "basic changes in public opinion occur because of changes in priorities"
reduced to the simplest and most significant form possible without loss of generality; "a basic story line"; "a canonical syllable pattern"
(mathematics) a set of entries in a square matrix running diagonally either from the upper left to lower right entry or running from the upper right to lower left entry
an oblique line of squares of the same color on a checkerboard; "the bishop moves on the diagonals"
a line or cut across a fabric that is not at right angles to a side of the fabric
(geometry) a straight line connecting any two vertices of a polygon that are not adjacent
at an angle; especially connecting two nonadjacent corners of a plane figure or any two corners of a solid that are not in the same face; "a diagonal line across the page"
a base hit on which the batter stops safely at first base
existing alone or consisting of one entity or part or aspect or individual; "upon the hill stood a single tower"; "had but a single thought which was to escape"; "a single survivor"; "a single serving"; "a single lens"; "a single thickness"
used of flowers having usually only one row or whorl of petals; "single chrysanthemums resemble daisies and may have more than one row of petals"