一线 yīxiàn front line
How to remember 一线: 一 one + 线 line = front line.
Characters
How it is used
- Two senses. (1) 'the front line / front-line': 战斗在一线 (zhàndòu zài yīxiàn) fighting on the front line, 一线城市 (yīxiàn chéngshì) a first-tier city, 一线医护 (yīxiàn yīhù) frontline medical staff. (2) 'a thread/sliver of': 一线希望 (yīxiàn xīwàng) a glimmer of hope, 一线生机 (yīxiàn shēngjī) a slim chance of survival.
- Sense (1) means the leading edge of action/rank; sense (2) is a tiny remaining amount, always something precious and faint.
- Both common; context makes clear which. Note the reading yīxiàn (tone-neutral 一).