ai·o·li (?-??l?, ?-??-)n. A rich sauce of crushed garlic, egg yolks, lemon juice, and olive oil.[Provençal : ai, garlic (from Latin allium; see allium) + oli, oil (from Latin oleum; see oil).]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.aïoli (a????l?; e?-) n (Cookery) garlic mayonnaise[from French ail garlic]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014ai?o?li (a??o? li, e??o?-) n. a garlic-flavored mayonnaise of Provence. [1895?1900;