Which term refers to using letter patterns to help understand a word's meaning and pronunciation?

The term that refers to using letter patterns to help understand a word's meaning and pronunciation is morphophonology. Morphophonology is the study of the interrelationship between phonology (the sound systems of a language) and morphology (the structure and meaning of words). It focuses on how the form of a word changes based on morphological rules and can aid in comprehending both the pronunciation and the meaning of words.

In this context, morphophonology involves analyzing letter patterns, such as prefixes, suffixes, and root words, which can provide clues about how to pronounce a word and what it means. For instance, recognizing the prefix "un-" can help a reader deduce that "undo" means to reverse something.

The other terms have different focuses: phonetics deals primarily with the sounds of speech and does not encompass letter patterns; graphology refers to the study of handwriting and its psychological implications, not necessarily applicable to understanding standard letter patterns in words; and orthography involves the conventional spelling system of a language but does not emphasize the relationship of spelling to meaning in the same way morphophonology does. Therefore, this choice accurately reflects the concept of using letter patterns to aid in word comprehension.