[1] : WordNet (r) 2.0

decline in quality
     n : process of changing to an inferior state syn: deterioration,
          declension, worsening
see also:
deterioration declension worsening 

Decline >> D Words
Decline, definition of term: Decline
decline_pag1.html

Quality >> Q Words
Quality, definition of term: Quality
quality_pag1.html

Quality Control >> Q Words
Quality Control, definition of term: Quality Control
quality+control_pag1.html

High Quality >> H Words
High Quality, definition of term: High Quality
high+quality_pag1.html

Quality Of Life >> Q Words
Quality Of Life, definition of term: Quality Of Life
quality+of+life_pag1.html