counterplan vs secret plan

counterplan and secret plan both are nouns.

Word	Noun	Adjective	Verb	Adverb
counterplan	Yes	No	No	No
secret plan	Yes	No	No	No

As nouns, secret plan is a hypernym of counterplan; that is, secret plan is a word with a broader meaning than counterplan:

counterplan: a plot intended to subvert another plot
secret plan: a secret scheme to do something (especially something underhand or illegal)

Other hypernyms of counterplan include game, plot.

counterplan (noun)	secret plan (noun)
a plot intended to subvert another plot	a secret scheme to do something (especially something underhand or illegal)