follow vs lag

follow is not a noun while lag is a noun.

Word	Noun	Adjective	Verb	Adverb
follow	No	No	Yes	No
lag	Yes	No	Yes	No

As verbs, lag is a hyponym of follow; that is, lag is a word with a more specific, narrower meaning than follow:

Other hyponyms of follow include dawdle, fall back, fall behind, tailgate, shadow, carry.

follow (noun)	lag (noun)
	the act of slowing down or falling behind
	one of several thin slats of wood forming the sides of a barrel or bucket
	the time between one event, process, or period and another

follow (verb)	lag (verb)
behave in accordance or in agreement with	throw or pitch at a mark, as with coins
keep informed	cover with lagging to prevent heat loss
keep to	hang (back) or fall (behind) in movement, progress, development, etc.
follow, discover, or ascertain the course of development of something	lock up or confine, in or as in a jail
grasp the meaning
imitate in behavior; take as a model
perform an accompaniment to
to travel behind, go after, come after
travel along a certain course
follow in or as if in pursuit
keep under surveillance
choose and follow; as of theories, ideas, policies, strategies or plans
to subscribe to someone's updates on social media
to be subscribed to updates from another user on social media
act in accordance with someone's rules, commands, or wishes
be the successor (of)
follow with the eyes or the mind
work in a specific place, with a specific subject, or in a specific function
accept and follow the leadership or command or guidance of
adhere to or practice
be later in time
come after in time, as a result
be next
to bring something about at a later time than
to be the product or result
come as a logical consequence; follow logically