星
セイ, ショウ, ほし, ぼし
star, spot, dot, mark
JLPT2 G2 S9 F844
The relevant seal inscription form is
晶
# (brightness) +
生
(fresh) → fresh, bright, invigorating starlight → *star*.
星
is a scribal form simplification.
[Full Kanji Etymology List]