10 strokes
                                                    
                        Jouyou kanji
            Taught in 9th grade
    
                                                    JLPT exam level N1
                                            nucleus, core, kernel
On'yomi
- カ - ク - stone (of a fruit) ②core (of an organization, team, etc.) ③nuclear weapons ④nucleus (of an atom) ⑤nucleus (of a cell) 
Character Breakdown
Common Words
                                    stone (of a fruit) ②core (of an organization, team, etc.) ③nuclear weapons ④nucleus (of an atom) ⑤nucleus (of a cell)
                                
                            References
| Unicode hex code | 6838 | 
| JIS X 0208 | 1-19-43 | 
| Nelson, A. Classic Nelson | 2254 | 
| Haig, J. New Nelson Japanese-English Character Dictionary | 2660 | 
| Halpern, J. New Japanese-English Character Dictionary | 927 | 
| Halpern, J. Kodansha Kanji Dictionary | 1162 | 
| Halpern, J. Kanji Learners Dictionary (Kodansha) | 628 | 
| Halpern, J. Kanji Learners Dictionary (Kodansha), 2nd edition (2013) | 836 | 
| Heisig, J. Remembering The Kanji | 1520 | 
| Heisig, J. Remembering The Kanji, Sixth Ed. | 1638 | 
| Gakken A New Dictionary of Kanji Usage | 577 | 
| O'Neill, P.G. Essential Kanji | 1608 | 
| Morohashi Daikanwajiten | 14743 | 
| Henshall, K. A Guide To Remembering Japanese Characters | 1074 | 
| Spahn and Hadamitzky Kanji and Kana | 1212 | 
| Spahn and Hadamitzky Kanji and Kana (2011 edition) | 1275 | 
| Hodges & Okazaki Japanese Kanji Flashcards | 1430 | 
| Kask, A. Tuttle Kanji Cards | 1348 | 
| Nishiguchi & Kono Kanji in Context | 986 | 
| Kodansha Kodansha Compact Kanji Guide | 1089 | 
| Maniette, Y. Les Kanjis dans la tete | 1534 | 
| Tuttle Dictionary Descriptor Code | 4a6.22 | 
| Four corner code | 4098.2 | 
| De Roo Code | 1862 |