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) is a test that helps doctors evaluate the strength and function of a childâs heart. The test uses sound waves to create a picture of the heart.