i love me some Romaine Lettuce!
Romaine or cos lettuce is the worst food in the world. 
oh yea? why is that?
cos" to the name of the Greek island of Cos, from which the lettuce was presumably introduced. Other authorities trace "cos" to the Arabic word for lettuce, "" .
It apparently reached Western Europe via Rome, as in Italian it is called "lattuga romana" and in French "", both meaning “Roman lettuce”. Hence the name “romaine”, the common term in North American English.
Ritual use.
For 3000 years (from at least 2700 BC),
Romaine lettuce
Romaine or cos lettuce ("Lactuca sativa" L. var. "longifolia") is a variety of lettuce that grows in a tall head of sturdy dark green leaves with firm ribs down their centers. Unlike most lettuces, it is tolerant of heat. In North America, romaine is sold as whole heads or as “hearts” that have had the outer leaves removed and are often packaged together. 
Commercially sold romaine lettuce has historically been the subject of product warnings by both U.S. and Canadian health authorities