We present an exact Eckart-embedded kinetic energy operator in bond coordinates for triatomic molecules. The kinetic energy operator is derived from the general equations of J. Chem. Phys. 107, 2813 (1997) for the Eckart frame and the method of Handy. The Coriolis terms of the Eckart-bond kinetic energy operator do not depend on the angle between the Eckart in-plane axis and the equilibrium bond vector. We compare the Eckart-bond kinetic energy operator to other kinetic energy operators and show that the Coriolis terms of the Eckart-bond operator are smallest. The Eckart-bond kinetic energy operator should be useful for calculating and analyzing ro-vibrational spectra. (C) 1997 American Institute of Physics.