a floating colony of hydrozoans of the genus Velella, having a vertical crest that is used as a sail.

Origin of velella

1825–35; < New Latin, equivalent to Latin vēl(um) sail + -ella -ella
Related formsve·lel·li·dous, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for velella

Historical Examples of velella