noun which may take the genitive case particle 'no', na-adjective
Describes a very high degree or intensity, often used with nouns like 緊張, 疲労, or 状態. Functions as a no-adjective or na-adjective.
He was so extremely nervous that he couldn't speak.
When you are extremely tired, it's better not to push yourself.
Before the interview, my hands were shaking from extreme tension.
He was extremely exhausted from days of overtime work.
最大 is used for measurable, quantitative maximums (最大値 'maximum value'), whereas 極度 is used for the intensity of a state or feeling.
軽度 means a mild or slight degree of something, the opposite of 極度's extreme, maximal degree.
Compound of 極 (きょく, 'extreme, pole') and 度 (ど, 'degree'). The meaning is transparent from its components.