What is a chemical bond?
A region of high electron density between two positively charged nuclei, such that a net attractive force results.
Typically, the covalent bond is rationalized on the basis of the sharing of 2 electrons between two atomic nuclei. The modern covalent bond is considered to be a region of high electron density between 2 positively charged atomic nuclei, such that internuclear repulsion is minimized, and a net attractive force results.
Ionic bonds fall outside this umbrella.