Synonyms of the word 
HOLLOWNESS → CONCAVENESS - CONCAVITY - EMPTINESS - FALSENESS - INSINCERITY - UNTRUTHFULNESS
hollowness
- n. the state or quality of being hollow.
concaveness
- n. the state of being concave; concavity.
concavity
- n. (uncountable) The state of being concave.
- n. (countable) A concave structure or surface.
emptiness
- n. The state or feeling of being empty.
falseness
- n. The characteristic of being false.
insincerity
- n. Property of being insincere, lacking sincerity or truthfulness.
untruthfulness
- n. The state of being untruthful; dishonesty.
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