1 tr. & intr. make or become soft or softer.
2 tr. (often foll. by up) a reduce the strength of (defences) by bombing or some other preliminary attack. b reduce the resistance of (a person).
Phrases and idioms:
softening of the brain a morbid degeneration of the brain, esp. in old age.
Derivatives:
softener n.
Useful english dictionary. 2012.