cdKK [ˌsiˈdi] ｜ /ˌsiˈdi/
GEPT 初級
C1noun
a compact disc, typically used for storing and playing digital audio recordings
I bought the new album on CD and listened to it in my car on the way home.
CD；光碟
C1noun
the basic unit of luminous intensity adopted under the International System of Units; equal to 1/60 of the luminous intensity per square centimeter of a black body radiating at the temperature of 2,046 degrees Kelvin
The brightness of this lamp is 700 cd, which is much brighter than the lamp over there.
燭光（cd，發光強度單位）
C2adjective
being one hundred more than three hundred
In the year 2023, the price of a standard CD player was only $100, however, the price of a CD player with advanced features was $400 and hence it was cd.