shield vs shell

shield and shell both are nouns.

Word	Noun	Adjective	Verb	Adverb
shield	Yes	No	Yes	No
shell	Yes	No	Yes	No

As nouns, shield and shell are synonyms defined as:

shield and shell: hard outer covering or case of certain organisms such as arthropods and turtles

Other synonyms of shield include carapace, cuticle.

As nouns, shell is a hyponym of shield; that is, shell is a word with a more specific, narrower meaning than shield:

shield: a protective covering or structure
shell: a metal sheathing of uniform thickness (such as the shield attached to an artillery piece to protect the gunners)

Other hyponyms of shield include nipple shield, plate, scale, shielding, shielding.

shield (noun)	shell (noun)
hard outer covering or case of certain organisms such as arthropods and turtles	the hard largely calcareous covering of a mollusc or a brachiopod
armor carried on the arm to intercept blows	hard outer covering or case of certain organisms such as arthropods and turtles
a protective covering or structure	ammunition consisting of a cylindrical metal casing containing an explosive charge and a projectile; fired from a large gun
	a metal sheathing of uniform thickness (such as the shield attached to an artillery piece to protect the gunners)
	the housing or outer covering of something
	a very light narrow racing boat
	a rigid covering that envelops an object
	the exterior covering of a bird's egg
	the hard usually fibrous outer layer of some fruits especially nuts
	the material that forms the hard outer covering of many animals

shield (verb)	shell (verb)
protect, hide, or conceal from danger or harm	remove from its shell or outer covering
hold back a thought or feeling about	remove the husks from
	use explosives on
	come out better in a competition, race, or conflict
	hit the pitches of hard and regularly
	look for and collect shells by the seashore
	fall out of the pod or husk
	create by using explosives