Attention deficit hyperactivity disorder (ADHD) should be diagnosed and treated in children as young as age 4, according to new guidelines from the American Academy of Pediatrics. Skip to main content
ephemeris. 1  a table showing the positions of a heavenly body on a number of dates in a regular sequence. 2  an astronomical almanac containing such tables. 3  Archaic. an almanac or calendar.
efÂ·ferÂ·ent fiÂ·bers. 1  those fibers conveying impulses to effector tissues (smooth, cardiac, or striated muscle, or glands) in the periphery; those fibers exiting a specific cell group (that is, efferent fibers of the basilar pons), used in reference to a cell group.