Synonyms of the word 
INSINCERITY → FALSENESS - HOLLOWNESS - UNTRUTHFULNESS
insincerity
- n. Property of being insincere, lacking sincerity or truthfulness.
falseness
- n. The characteristic of being false.
hollowness
- n. the state or quality of being hollow.
untruthfulness
- n. The state of being untruthful; dishonesty.
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