Read aloud as English letters 'C-D'. Comes from 'cooldown' (冷却时间). Conjugates Chinese-style: 在 CD (on cooldown), CD 好了 (cooldown is up), 缩 CD (reduce cooldown).
mistakes
Don't confuse with the older 'compact disc' meaning (now obsolete in everyday speech) or 'cross-dresser' English slang. In gaming context CD is unambiguously cooldown.
