noun, plural por·to·la·nos, por·to·la·ni [pawr-tl-ah-nee, pohr-] /ˌpɔr tlˈɑ ni, ˌpoʊr-/.
a descriptive atlas of the Middle Ages, giving sailing directions and providing charts showing rhumb lines and the location of ports and various coastal features.
Origin of portolano
Also called rutter.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for portolano
Historical Examples of portolano
A sea-chart—probably a portolano—is mentioned as early as the account of the Crusade of St. Louis, in 1270.The Chronicle of the Discovery and Conquest of Guinea
Gomes Eannes de Azurara