gibbous

当然ですが2001 A Space Odysseyには天体についての単語が多くでてきます。 "gibbous" もその一つで次ぎの様に２度出てきたので覚える事にします。
Under its automatic controls, the shuttle was sliding down the starlit sky, toward that barren landscape glimmering in the light of the great gibbous Earth.
...
Inside Discovery, David Bowman carefully centered the cross-wires that aligned the antenna on the gibbous Earth.
辞書で意味を調べます。
・Merriam-Webster's Learner's Dictionary: of the moon or a planet : seen with more than half but not all of the apparent disk illuminated
・Vocabulary.com: (used of the moon) more than half full: On Christmas, many will be looking skyward and wondering what that brilliant silvery "star" is hovering just above the waxing gibbous moon.
東京の夜の空は星は余り見えませんが、月はさすがに見えます。今度夜の空を見る時に "gibbous moon" が出ているか気にして、この単語を覚えましょう。