Final answer:
The italicized word 'girded' in the sentence is a verb, which expresses an action or state of being.
Step-by-step explanation:
The italicized word in the sentence 'Stephen girded his sword upon his armor' is verb. A verb is a word that expresses an action or state of being. In this sentence, the word 'girded' is the past tense form of the verb 'gird', which means to surround or secure something tightly. It is the action Stephen is performing by putting his sword on his armor.
Learn more about part of speech