We found one dictionary that defines the word single shells:

General (1 matching dictionary)

1. single shells: Vocabulary.com

(Note: See single_shell as well.)

Definitions from WordNet (single shell) ▸ noun:  a shell for a single oarsman ▸ Also see single_shell ▸ Words similar to single shells ▸ Usage examples for single shells ▸ Idioms related to single shells ▸ Wikipedia articles (New!) ▸ Words that often appear near single shells ▸ Rhymes of single shells ▸ Invented words related to single shells