>Conceal or disguise one’s true feelings or beliefs.
>To hide under a false appearance
Dissemble (from Latin dissimulare, meaning “to hide or conceal”) stresses the intent to deceive, especially about one’s own thoughts or feelings, and often implies that the deception is something that would warrant censure if discovered.
Example
Children learn to dissemble at a surprisingly early age
He dissembled happiness at the news that his old girlfriend was getting married to someone else