We found 2 dictionaries that define the word single letter:

General (1 matching dictionary)

1. single-letter: Wordnik

Art (1 matching dictionary)

2. Glossary of Stamp Collecting Terms (No longer online)

▸ Words similar to single letter ▸ Usage examples for single letter ▸ Idioms related to single letter ▸ Wikipedia articles (New!) ▸ Words that often appear near single letter ▸ Rhymes of single letter ▸ Invented words related to single letter