declension (n.)
- abnegation
- accidence
- affix
- affixation
- allomorph
- cascade
- cataract
- chute
- collapse
- comedown
- conjugation
- contradiction
- crash
- cutting
- debacle
- debasement
- decadence
- decadency
- deceleration
- declination
- decline
- decrescendo
- deformation
- degeneracy
- degeneration
- degradation
- demotion
- denial
- depravation
- depreciation
- deprivation
- derivation
- derogation
- descension
- descent
- deterioration
- devolution
- dilapidation
- diminuendo
- disagreement
- disclaimer
- disobedience
- dissent
- dive
- down
- downfall
- downgrade
- downpour
- downturn
- drop
- dropping
- dwindling
- dying
- ebb
- fading
- failing
- fall
- formative
- gravitation
- inclination
- infix
- inflection
- involution
- lapse
- morph
- morpheme
- morphology
- morphophonemics
- nay
- negation
- negative
- nix
- no
- nonacceptance
- noncompliance
- nonobservance
- paradigm
- plunge
- pounce
- prefix
- prefixation
- radical
- rapids
- recantation
- refusal
- regression
- rejection
- remission
- repudiation
- retention
- retreat
- retrogression
- root
- ruination
- slippage
- slowdown
- slump
- stem
- stoop
- subsidence
- suffix
- suffixation
- swoop
- theme
- turndown
- unwillingness
- wane
- waterfall
- withholding
