shield

(noun) a protective covering or structure.

(noun) armor carried on the arm to intercept blows. Synonyms: buckler.

(noun) hard outer covering or case of certain organisms such as arthropods and turtles. Synonyms: carapace, shell, cuticle.

(verb) protect, hide, or conceal from danger or harm. Synonyms: screen.

(verb) hold back a thought or feeling about. Synonyms: harbor, harbour. Examples: "She is harboring a grudge against him."