卵, 玉子, たまご
Only 卵
1. eggs, egg, spawn, roe
玉子 oft. used in cooking
2. (hen's) egg
3. (an expert) in the making
4. beginning, origin, infancy
彼は医者の卵だ。
卵, 殻, 稃, かい, かいご
Archaism
egg, eggshell
彼は医者の卵だ。
卵, らん
Zoology term
ovum, ovule, egg cell
彼は医者の卵だ。
が
Particle
1. indicates sentence subject (occasionally object)
2. indicates possessive (esp. in literary expressions)
Conjunction
3. but, however, still, and
after the volitional form of a verb
4. regardless of, whether (or not)