"Dictionary of the English Language" by Samuel Johnson (1755)

Drawing upon contemporary literature and historical sources, Samuel Johnson pieced together his Dictionary of the English Language over the course of nine years of intense labor and financial hardship. Johnson's Dictionary was the first English dictionary of its kind and provided comprehensive grammar lessons, a history of the English language, and definitions for most known English words. Johnson's dictionary was widely regarded as the preeminent dictionary for the centuries following its publication and was adopted for the instruction of English in colonies across the globe.