You might be forgiven for assuming that complacence and complaisance mean the same thing. Maybe they’re alternative spellings for the same word or something. It turns out, though, these are different words with almost opposite meanings.
complacence kəm-‘plā-sᵊn(t)s. n.
- Calm or secure satisfaction with oneself or one’s lot
- Unconcern
Example: Sam’s complacence with the boss’s request led to getting fired.
complaisance kəm-‘plā-sᵊn(t)s. n.
- Disposition to please or comply
- Affability
Example: Sam’s complaisance with the boss’s request led to a promotion.
Complacence is a common word generally used to describe a lack of interest or concern. It usually carries a negative connotation. Complacence suggests a lack of motivation to improve circumstances or react to danger.
By contrast, complaisance is a more obscure word used to describe a positive demeanor that happily acquiesces to circumstances or commands.
So, rather than being the same word, complacence and complaisance are actually near antonyms. They mean roughly the opposite of each other. And depending on the speaker’s dialect, complacence and complaisance could also be considered homophones. That means they sound the same.
Obviously, there’s a real danger for misunderstandings. This is especially true since one word is often used as a criticism while the other is a compliment.
Recommendation
Our recommendation is to reserve the term complaisance for written communication with other word people. If you’re speaking, consider a safer synonym like affability or acquiescent.
Source: Merriam-Webster (complacence, complaisance)