Merriam-Webster's Collegiate® Dictionary, 11th Edition
LARK
I. noun
Etymology: Middle English laveroc, laverke, from Old English lāwerce; akin to Old High German lērihha lark Date: before 12th century any of a family (Alaudidae) of chiefly Old World ground-dwelling songbirds that are usually brownish in color,
II. noun
Etymology: 3lark
Date: circa 1811
a source of or quest for amusement or adventure ,
III. intransitive verb
Etymology: probably alteration of lake to frolic
Date: 1813
to engage in harmless fun or mischief, larker noun