course vs lesson

course and lesson both are nouns.

Word	Noun	Adjective	Verb	Adverb
course	Yes	No	Yes	Yes
lesson	Yes	No	No	No

course (noun)	lesson (noun)
a mode of action	a task assigned for individual study
education imparted in a series of lessons or meetings	a unit of instruction
facility consisting of a circumscribed area of land or water laid out for a sport	punishment intended as a warning to others
(construction) a layer of masonry	the significance of a story or event
part of a meal served at one time
a connected series of events or actions or developments
a body of students who are taught together
general line of orientation
a line or route along which something travels or moves

course (adverb)	lesson (adverb)
as might be expected