Examples:
The poor dog weakened daily as the disease spread through its body.
Another defeat in the parliament could weaken the president's ability to govern.
Prolonged exposure to vibration can weaken aircraft components.
The prisoner's resistance weakened after seven days.
Mappings:
VerbNet: other_cos-45.4
FrameNet: Cause_change_of_strength
PropBank: weaken.01
WordNet 3.0 Sense Numbers: 1, 2, 3, 4, 5