Εννοια

1. An action or statement in response to a stimulus or other event.
2. A transformation in which one or more substances is converted into another by combination or decomposition.
3. Reactionary politics; a period in which reactionary thought or politics is resurgent or dominant.
4. Unpurposeful behavior.
5. An icon or emoji appended to a posted message by a user to express their feeling about it.