5 Old HSK word(s): ☊核 ** C ☊核桃 ** D ☊核武器 ** D ☊核心 ** D ☊考核 ** D
查核* * 肺结核* * 复核* * 果核* * 核* * 结核* * 热核* * 审核* * 无核* * 细胞核* *

Definitions from Unihan Copyright © 1991-2015 Unicode® Inc. All rights reserved.

细 fine, tiny / slender, thin
胞 womb, placenta, fetal membrane
核 seed, kernel, core, nut / atom

Hsk Characters: 核 *
HSK -Characters and beyond:
GbBig5EngRadMegaTripleMultilingual
核 6838 + 核 + + seed, kernel, core, nut / atom 木 亥 Tree 亥 (STERNZEICHEN SCHWEIN) 【◎Fix:◎he2;◎hu2】 +

Korean:

核 + 核 씨 핵 (씨: a seed) or 핵 핵 (핵: the core, the nucleus)
覈 + 核 핵실할 핵, 겨무거리 핵, 씨 핵, 액색할 핵
2 NHSK word(s): 核心* 5 he2 xin1core/ nucleus 考核* 6 kao3 he2to examine/ to check up on/ to assess/ to review/ appraisal/ review/ evaluation
KOREAN6000 word(s):
1 KOREAN 2500 New HSK words):
核心 + héxīn 핵심. haegsim.
0 KOREAN Sentence(s):