In order to provide income over the lifetime of the retiree, the TDF is designed to increasingly invest in deferred annuities as the TDF reaches its target retirement date and investors in the TDF get older.
Freebase(0.00 / 0 votes)Rate this definition: Echocardiography. Echocardiogram, often referred to cardiac echo or simply an echo is a sonogram of the heart. Echocardiography uses standard two-dimensional, three-dimensional, and Doppler ultrasound to create images of the heart.
An echocardiogram (echo=sound + card=heart + gram=drawing) is an ultrasound test that can evaluate the structures of the heart, as well as the direction of blood flow within it.