Final answer:
A culture where people say what they mean and mean what they say, striving for clarity in communication, is known as a low-context culture.
Step-by-step explanation:
The term that best describes a culture in which people say what they mean and mean what they say, and always strive to be clear when speaking, is a low-context culture. In low-context cultures, communication is direct and explicit, with less reliance on situational factors and shared knowledge. The messages conveyed are unambiguous, with the intention that they be understood without the need for much contextual information. This contrasts with high-context cultures, where communication relies heavily on implicit understanding, non-verbal cues, and shared experiences.