1. In chemistry, a base that does not completely dissociate in aqueous solution and only partially ionizes to produce hydroxide ions
Ammonia is a weak base commonly used in laboratory experiments
Amônia é uma base fraca comumente usada em experimentos de laboratório
2. Figuratively, a foundation or support that is unstable or unreliable
The project was built on a weak base and eventually failed
O projeto foi construído sobre uma base fraca e eventualmente falhou