A keyword mnemonic is an aid to hel

A keyword mnemonic is an aid to help students learn new vocabulary words. When using this strategy, the learner makes a connection between the new word and an image involving a related word that serves as a "key" to remember the new word. For example, a student of French could remember that pain is the French word for bread by vividly picturing a loaf of bread in a pan.
Does this method really help learners know the new words? Does it truly help expand their vocabularies?
The answer depends on what we mean by knowing (Calfee & Drum, 1986). If knowing means giving the definition of the word when asked to do so, the answer would be yes. If knowing means seeing the word in a sentence in a book, thinking about it for a moment, recalling the meaning, and then inserting that definition into the context so that we can understand the sentence, then the answer would still be yes. These are valid definitions of knowing. However, if knowing a word means that we can use the word in our conversations and in our thinking and recognize all possible contexts of the word (Cronbach, 1943), then it is not equally obvious that the keyword method helps students use new words effectively.
What the research shows is that students who use mnemonic strategies are generally not at a disadvantage compared to students who use other strategies, such as semantic analysis or free study, when they are asked to give or infer the meaning of words a week or so after studying them. In most cases, they do better. However, some research suggests that the strategy is not as effective as other methods for long-term retention and for making the words a part of the student's working vocabulary. (For a review of the research, see Stahl & Fairbanks, 1986.)
It is probably best to regard mnemonic methods as very powerful precomprehension strategies. Being able to recognize the meaning of a word is useful - whether this is accomplished by recalling it mnemonically or by looking it up in a dictionary; but to know a word in its fullest sense, students must use that word as concretely as possible in many contexts, so that it can be meaningfully integrated with appropriate information and appropriately retrieved from long-term memory.