n. The browning and death of a plant shoot starting at the tip, due to either disease or climate conditions
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a disease of plants characterized by the gradual dying of the young shoots starting at the tips and progressing to the larger branches
Word Usage
"The direst predictions come from the British meteorological office's Hadley Center, where a team led by Peter Cox forecast a massive "dieback" of plants, killing the rain forest by 2100."