Egg(s); spawn or roe of animals; the general noun for eggs used in cooking and biology.
朝ごはんに卵を二つ食べた。
I ate two eggs for breakfast.
イクラは魚の卵の一種だ。
Ikura is a type of fish egg (roe).
水槽で魚の卵が孵るのを待っている。
We're waiting for the fish eggs in the tank to hatch.
Specifically hen's egg used in cooking; often written as 玉子 in culinary contexts (e.g., tamagoyaki).
玉子焼きを作るために卵を三個使った。
I used three eggs to make tamagoyaki (rolled omelet).
料理のレシピでは卵を『玉子』と表記することが多い。
In recipes, eggs are often written as '玉子'.
生卵をご飯にかけて食べるのが好きだ。
I like to eat raw egg over rice.
Used in the phrase '…の卵' to mean someone who is a budding or future professional (e.g., 'a doctor in training').
彼は医者の卵として大学で勉強している。
He is studying at university as a future doctor (a doctor in training).
まだ作家の卵だが、作品に独自性がある。
He's still an aspiring writer, but his work has originality.
Beginning, origin, or infancy; used metaphorically to describe something in an early or undeveloped stage.
この企画はまだ卵の段階で、詳細はこれから詰める予定だ。
This project is still at the early stage; details will be worked out later.
新しい技術は卵の段階を脱してようやく実用化が始まった。
The new technology has moved beyond the initial stage and is finally beginning to be put to practical use.