Contextual explanation: Expression of protest or rejection. 
À bas is best understood as an action—specifically, a forceful verbal act aimed at rejecting, protesting, or calling for the end of an idea, authority, or institution. It is commonly used in demonstrations or political contexts to signal collective opposition and the desire to bring about the downfall or removal of something perceived as unjust or unwanted.

Themes: Dissent and Protest. 
The theme central to À bas is protest, as it embodies the collective voice of dissent against established norms, authorities, or policies. It is a rallying cry that unites individuals around a shared cause, often in pursuit of social or political change.

Nuance: Catalytic rejection. 
What distinguishes À bas within its category is its catalytic nature—it is not merely an expression of disapproval, but a call to action that seeks to mobilize others toward the active rejection or overthrow of a target. This nuance highlights its role as both a linguistic and social tool for initiating change.