IC analysis
abnegation
accidence
affix
affixation
allomorph
bound morpheme
cascade
catabasis
cataract
chute
collapse
comedown
conjugation
contradiction
crash
cutting
debacle
debasement
decadence
decadency
decay
deceleration
declination
declinature
decline
decline and fall
declining
decrescendo
defluxion
deformation
degeneracy
degenerateness
degeneration
degradation
demotion
denial
depravation
depravedness
depreciation
deprivation
derivation
derogation
descending
descension
descent
deterioration
category
class
family
inflection
inflexion
/etc/skel
atavism
devel
retrogradation
retrogression