which can help readers define words?

pronunciations
parts of speech
etymological patterns
stressed syllables

All of the options listed can help readers define words in different ways:

1. Pronunciations: Knowing how to pronounce a word correctly can aid in understanding its meaning. Pronunciations can be indicated using symbols or phonetic transcriptions.

2. Parts of speech: Identifying the part of speech of a word, such as noun, verb, adjective, or adverb, can provide insight into its usage and meaning.

3. Etymological patterns: Understanding the origin and history of a word can shed light on its meaning. Etymology involves studying the roots, prefixes, and suffixes of words and how they contribute to their meaning.

4. Stressed syllables: Knowing which syllables in a word are stressed can help with pronunciation and understanding its meaning. Stress patterns can vary across different languages and can affect word meaning and usage.