round shape vs whirl

round shape and whirl both are nouns.

Word	Noun	Adjective	Verb	Adverb
round shape	Yes	No	No	No
whirl	Yes	No	Yes	No

As nouns, whirl is a hyponym of round shape; that is, whirl is a word with a more specific, narrower meaning than round shape:

round shape (noun)	whirl (noun)
a shape that is curved and without sharp angles	a usually brief attempt
	the act of rotating rapidly
	confused movement
	the shape of something rotating rapidly

round shape (verb)	whirl (verb)
	flow in a circular current, of liquids
	turn in a twisting or spinning motion
	cause to spin
	fly around
	revolve quickly and repeatedly around one's own axis