invalid
An invalid invalid should not get benefits.
The sentence argues that someone who falsely claims disability should not receive benefits.
Meanings
not legally or factually valid; lacking force or correctness
- The contract was deemed invalid.
- An invalid argument cannot establish its conclusion.
a person made weak or disabled by illness or injury, often chronically
- She nursed her invalid mother for a decade.
- After the war, many veterans returned as invalids.
Word origin
Both senses descend from Latin invalidus ('not strong, weak'), formed from in- ('not') + validus ('strong, healthy'). The adjective sense ('not strong, not legally binding') and the noun sense ('a sick or disabled person') are essentially the same word — the noun is just the adjective applied to people. The stress shift between the two is a pure English innovation.
Fun fact
The shift in stress between the adjective and noun reflects how English sometimes creates two words from one Latin source. The Latin invalidus had a single accent pattern; English moved the stress in the noun to mark it as a different word — the same trick that produces 'record/record', 'present/present', and dozens of other heteronymic pairs.