Final answer:
The term for words in a graded membership that share at least one meaning in common is Co-hyponymy.
Step-by-step explanation:
On a graded membership, when each word has at least one meaning in common, it is called Co-hyponymy. This term refers to a set of words that all belong to the same category and have some shared semantic characteristics. An example of co-hyponymy in English could be the words "apple", "banana", and "cherry", which are all types of fruit. They share a common category but each represent different items within that category. Another example is the set of words that describe colors like "red", "blue", and "green"; they are all co-hyponyms within the category of color.
In the context of language learning and word usage, co-hyponyms can be very useful for understanding the relationships between words and the nuanced differences between their meanings. Knowing that certain words share a common characteristic helps learners see the connections and organize their knowledge of language more effectively.