A bond in which one atom contributes both bonding electrons to a covalentbond

A coordinate bond

Explanation: A chemical bond is a force of attraction between two or more atoms of elements. Covalent bond is a type of chemical bond that occurs between non-metal atoms. It occurs as a result of sharing of electrons between the non-metal atoms. Atoms involved in covalent bond formation may contribute equally to the bond formation or the electrons shared may come form one of the atoms. When the electrons shared in a covalent bond are derived from one atom, then the covalent bond is known as a coordinate bond.