VAK-yoo-us
(adjective) Lacking thought, intelligence, or meaning.
The President’s speech was filled with vacuous slogans and lacked substance.
Fun Fact
Vacuous is closely related to the word “vacuum”—think of something hollow or devoid of content. It’s frequently used in media criticism to describe interviews, reality TV dialogue, or political statements that sound nice but say nothing.
DISS-uh-nuhnt
(adjective) Lacking harmony; clashing or conflicting in sound, ideas, or opinions.
The debate grew heated as their dissonant perspectives on technology’s role in society collided.
Derived from the Latin dissonare, meaning “to sound apart,” dissonant entered English in the 15th century through Middle French. Originally used to describe unpleasant or clashing sounds in music, it later expanded to describe intellectual or emotional discord—when ideas, beliefs, or behaviors fail to align.
Fun Fact
In psychology, the word dissonant is central to the theory of cognitive dissonance—a concept introduced by psychologist Leon Festinger in the 1950s. It describes the mental discomfort we feel when our actions and beliefs don’t match. For example, knowing that junk food is unhealthy but eating it anyway creates a dissonant feeling your brain wants to resolve. This theory reshaped modern understanding of motivation, explaining why people often change their beliefs to match their behavior rather than the other way around.