Which word best fits the definition of being blunt or dull in perception?

The term that best fits the definition of being blunt or dull in perception is "obtuse." This word is often used to describe someone who is slow to understand or lacks sharpness in their thinking, which aligns perfectly with the idea of dullness in perception. When someone is described as obtuse, it implies a certain insensitivity or inability to grasp more nuanced ideas or concepts, reflecting a lack of keenness in mental acuity or insight.

In contrast, the other options have different meanings that do not align with the definition given. "Officious" generally refers to someone who is overly eager to offer unwanted help or advice, often coming off as intrusive. "Obfuscate" means to confuse or make something less clear, which does not relate to the state of being dull in perception. "Nadir" refers to the lowest point of something, often in a figurative sense, such as the lowest point of a person's fortunes or a celestial object. None of these terms capture the essence of dullness or bluntness in perception like "obtuse" does.