The word "duncelike" is not very common in modern vocabulary, but there are some synonyms that can be used to convey the same meaning. Some possible alternatives include "foolish," "simple-minded," "stupid," "naive," "unwitting," and "clueless." These words all carry a sense of lacking intelligence or awareness, as if the person is unable to understand or perceive what is happening around them. Of course, it is important to use such words with caution, as they can be seen as derogatory or insulting if used inappropriately. It is always best to choose words that are precise and accurate, and to consider the context and tone in which they will be used.