Leaf. A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants.eaf (noun). something which is like a leaf in being wide and thin and having a flat surface, or in being attached to a larger body by one edge or end; as : (a) A part of a book or folded sheet containing two pages upon its opposite sides.
Production on Vikings season 4 is set to begin this spring in Ireland (presumably for an early 2016 premiere), while its third season will wrap up in about a month, on April 23rd.
Season 5. Season 4 of Vikings premiered on February 18, 2016 on History in Canada and in the United States and concluded on February 1, 2017. It is the final season to feature Travis Fimmel as King Ragnar. This season, consisting of 20 episodes, was split into two ten-episode parts with the first part airing from February 18 to April 21, 2016 while the second part aired from November 30, 2016 to February 1, 2017.