Age-related macular degeneration (AMD or ARMD) is the most common cause of vision loss in those aged over 50. It causes a gradual loss of central (but not peripheral) vision. Central vision is needed for detailed work and for things like reading and driving. The disease does not lead to complete blindness.
Definition of Dissonance Dissonance is the use of impolite, harsh-sounding, and unusual words in poetry. In other words, it is a deliberate use of inharmonious words, phrases, or syllables intended to create harsh sounding effects.
from The American HeritageÂ® Dictionary of the English Language, 4th Edition. 1  Jarring, discordant sound; dissonance: heard a cacophony of horns during the traffic jam. 2  The use of harsh or discordant sounds in literary composition, as for poetic effect.