decline

(noun) change toward something smaller or lower. Synonyms: diminution.

(noun) a condition inferior to an earlier condition; a gradual falling off from a better state. Synonyms: declination.

(noun) a gradual decrease; as of stored charge or current. Synonyms: decay.

(noun) a downward slope or bend. Synonyms: descent, declivity, fall, declination, declension, downslope.

(verb) grow worse. Synonyms: worsen. Examples: "Conditions in the slum worsened."

(verb) refuse to accept. Synonyms: refuse, reject, pass up, turn down. Examples: "He refused my offer of hospitality."

(verb) show unwillingness towards. Synonyms: refuse. Examples: "He declined to join the group on a hike."

(verb) grow smaller. Synonyms: go down, wane. Examples: "Interest in the project waned."

(verb) go down. Examples: "The roof declines here."

(verb) go down in value. Synonyms: slump, correct. Examples: "The stock market corrected." "Prices slumped."

(verb) inflect for number, gender, case, etc., "in many languages, speakers decline nouns, pronouns, and adjectives".