芯
xīnxìn HSK7

pith from rush (juncus effusus)

芯 xīn frequency
pith noun
(bound form) the pith of the rush plant (used as a lampwick)

他小心地修剪了油灯的灯芯。

tā xiǎo​xīn de xiū​jiǎn le yóu​dēng de dēng xīn.

He carefully trimmed the wick of the oil lamp.

芯 xìn
core noun
the internal part or center of an object, such as a wick, fuse, or lead

这支圆珠笔的笔芯已经没有墨水了。

zhè zhī yuán​zhū​bǐ de bǐ xìn yǐ​jīng méi​yǒu mò​shuǐ le.

The refill of this ballpoint pen has run out of ink.

Frequency
Character
Written text
2,539th most common 18.4 per million
Movie subtitles
2,366th most common 10.8 per million appears in 3% of films
Word
Movie subtitles
0.660 per million appears in 0% of films
Written text
17.3 per million

Details
HSK 3.0
Level 7
Strokes
7
Unicode
U+82AF

Sources
Definitions
CC-CEDICT
Frequency data
MTSU Chinese text computingSUBTLEX-CHBCC Corpus (BLCU)