Vocabulary knowledge is defined as the ability to go from the printed form of a word to its meaning.

Recognized By

The student does not understand the meaning of words commonly understood by students of her age level. The student’s weakness may be reflected in poor performance on tests of vocabulary knowledge. Inadequate vocabulary causes reduced reading comprehension.


Reading researchers and reviewers of reading research have reported that a strong relationship exists between vocabulary knowledge and comprehension (Blachowicz, Fisher, Ogle, & Watts-Taffe, 2006; Davis, 1942, 1944; Pearson, Hiebert & Kamil, 2007). Authorities have differing notions about what it means to know the meaning of a word. Part of the problem is that one may know the meaning of a word at five different levels or stages. These stages are listed here from lowest to highest level of vocabulary knowledge.

  1. A student has no recognition of a word. Indeed, she may never have seen it before.
  2. A student has heard of the word (that is, recognizes that it is a word) but has no knowledge of its meaning.
  3. A student recognizes the word in context and has a vague understanding of its meaning.
  4. A student knows well the meaning of the word in the context in which it appears.
  5. A student knows the multiple meanings of the word (if they exist) and can actually use the word in thinking, speaking, or writing.

Knowledge at level 2 is usually required for a student to decode a difficult word, while knowledge at levels 3 or 4 is required for the student to comprehend what she reads. Thus, one of the important reasons that teachers teach vocabulary is to enable students to understand written material. Adequate decoding ability alone will not enable a student to understand material in either a narrative or content- area book.

Assessing Vocabulary Knowledge

There are two main purposes for assessing a reader’s vocabulary knowledge. The first is to assess the general level of a reader’s vocabulary knowledge to determine if it is sufficient for her grade level. The second purpose is to determine if she knows the meaning of a specific word or set of words to guide immediate instruction.

One method of measuring the general level of a student’s vocabulary is to look at the results of the vocabulary subsection of a standardized test. When a standardized exam contains a subsection that measures the student’s vocabulary knowledge, the student’s performance on that section of the exam is reported in norms. Those norms can be used to estimate the student’s general level of vocabulary knowledge. For example, a common norm used to describe performance on standardized exams is called a grade equivalent score. This score is the grade level of the students in the norm group who performed the same on the vocabulary exam as your student performed on the vocabulary exam. This and other norms can be used to get an idea of the student’s general vocabulary level.

Some care needs to be taken when using the results of standardized achievement tests. The most widely used format is the multiple-choice measure in which the student selects, from among several choices, a short definition or a synonym for a target word. Such tests usually measure vocabulary knowledge at level 3, rather than the student’s full continuum of word knowledge. If you use such a test, examine the students’ raw scores to see if they are above a level that could have been made by chance guessing. A number of standardized reading achievement tests may allow a student who may essentially not read at all to score well into the norms and to have a vocabulary achievement score well above her actual vocabulary ability. Some students do poorly on standardized tests of vocabulary knowledge because they lack sufficient decoding ability. If a student does much better on an individually administered oral vocabulary test, you may then assume that a lack of adequate word-attack skills is contributing to her low score on the standardized test.

Another method of testing students’ general knowledge of vocabulary is to ask them the meaning of several words that appear in textbooks at their grade level. This will give you an estimate of how well the students’ vocabulary knowledge matches their grade level. However, it will not allow you to compare the vocabulary achievement of your students with those in the country as a whole. If you are a teacher in a school with a large group of students from a low socioeconomic level, this method of testing vocabulary knowledge may give you “tunnel vision,” because students with only a normal vocabulary may appear very good in comparison to other students in the class.

When there is a need to determine if a student knows the meaning of a specific word rather than her general vocabulary level, just ask her to tell you what the word means. Unfortunately, that is difficult to do with a large group of students. Two methods that can be used to determine if a group of students knows the meanings of a specific set of words are a self-check assessment or a multiple-choice assessment. In the self-check assessment, the student simply looks at a list of words and places a check mark by the words of which she knows the meaning. In the multiple-choice assessment, a teacher provides the target word and a choice of several possible meanings or synonyms.

The self-check assessment is easy to make, but it is subject to students being overly optimistic in what they think they know or underestimating what they know if they are insecure. The multiple-choice assessment provides more reliable evidence of what the student knows, but good multiple-choice items can be difficult to write. Multiple-choice assessments also allow guessing and provide a hint in that the meaning of the vocabulary word is one of the choices.

Teaching Vocabulary Knowledge

The main goal when providing reading vocabulary instruction is to develop an association between the printed form of a word and its meaning or meanings, in the case of a word with more than one meaning. It appears the deeper and richer that association, the more likely the reader will remember the meaning of the word when she encounters it in a passage she is reading.

An issue that affects word-meaning instruction is deciding which words to teach. The short-term answer is fairly simple: Teach the meaning of words that will be important in the material being read today. If the student does not know the meaning of words that are essential to understanding what is currently being read, then those words need to be the target of current vocabulary instruction.

There is also a need for all students to develop a wide vocabulary to use in the variety of reading situations they might encounter. No word lists can cover all possible reading situations. However, there are list of words that apply to more specific situations. Word lists to help prepare a student to take the Scholastic Aptitude Test or words that all fit under the study of U.S. history are two examples. A list of basic sight words can be used to find high frequency words that have concrete meanings associated with them. These words can be used for instruction of students whose word-meaning vocabulary knowledge is well below that of their peers. A list of words considered to be essential for each grade level has been developed by R. J. Marzano, J. S. Kendall, and D. E. Paynter (2005). It may be useful to teachers wanting to provide more general but grade-appropriate vocabulary instruction.

Researchers do not agree on how most of a student’s vocabulary knowledge is learned. Some evidence shows that a reader learns the meaning of more words from reading and using language than by direct instruction of vocabulary words (Nagy, Herman, & Anderson, 1985). This would seem to indicate that the number of words taught through direct instruction will probably not be enough to develop the level of vocabulary knowledge demonstrated by competent adult readers. However, Andrew Biemiller (2001) has reported that 80% of the root words students learn by sixth grade are the result of direct instruction. Regardless of the number of words learned through this method, no reading research has argued against providing direct instruction in vocabulary. A complete reading instruction program should include opportunities for direct and indirect growth in word knowledge.

Teaching word meanings in isolation should be avoided. The large number of multiple-meaning words makes teaching words out of context an uncertain situation. Students may successfully learn one meaning of a word but find that the meaning does not apply in the story or textbook that they are currently reading.

ELL Students and Vocabulary Instruction

ELL students generally can benefit from development of their English word-meaning vocabulary. The instruction for vocabulary development can be through both direct and indirect approaches. However, copying isolated vocabulary words and looking up the definitions in a dictionary is not recommended. The words in the dictionary definitions may not be familiar to ELL students, resulting in frustration and no meaningful learning (Echevarria, Vogt, & Short, 2008). Echevarria and colleagues do recommend the use of the Oxford Picture Dictionary for the Content Areas (Kauffman & Apple, 2000) as a resource for ELL students and vocabulary instruction.

Teaching ELL students the meaning of words that will be important in the material currently being read is critical. The first step in introducing those words should be to find out if your second-language learners have the necessary background knowledge to understand the new vocabulary. Developing the general vocabulary knowledge of ELL students is also important. A list of 2,000 to 2,500 basic English vocabulary words is suggested (Folse, 2004). The list is made up of frequently occurring words in the English language.

Several studies have demonstrated the success of using words in the ELL student’s first language that are similar to English words in vocabulary instruction (Carlo, August, & McLaughlin, 2004). The use of these words, which are known as cog- nates, has also been recommended for content-area instruction of ELL students (Bravo, Hiebert, & Pearson, 2007).