decline
de-cline
verb
To politely refuse an invitation, offer, or request.
"She had to decline the job offer."
noun
A gradual and continuous loss of strength, numbers, or quality.
"The area saw a sharp decline in population."
Thesaurus
Synonyms: declination, downslope, fall, declension, declivity, descent, diminution, refuse, pass up, turn down, reject, decay
Antonyms: accept, acclivity, ameliorate, ascent, better, climb, consent, go for, have, improve, improvement, meliorate