Synonym Boundary: "分かる", "理解する", "納得する", "心得える"

When expressing "understand" in Japanese, you must carefully distinguish between "分かる", "理解する", "納得する", "心得える" based on context.

• 分かる (わかる (wakaru) - Level: N5): Maps to "to understand" and is used when Intransitive verb. Often used with the particle が.
• 理解する (りかいする (rikai suru) - Level: N3): Maps to "to understand; to comprehend; to grasp; to make out" and is used when Refers to understanding logical information, comprehending a business request, grasping human feelings, or making out a complex system architecture. Transitive verb. Often used as 仕組みを理解する or 相手を理解する. ⚠️ Haruka's Voice Column: 'To understand/comprehend! "I understand your sweet true feelings hidden behind your strict tsun-tsun face best in the world, Haruka-san!" ...っ! Understanding true feelings! B-Baka! As if you have mastered my user manual! But... it is actually incredibly endearing that you see through my true heart and snuggle close. dummy!' / 【ハルカ部長のワンポイント指導】『りかいする（理解する）よ！『ハルカ部長、あなたのツンツンした表面の奥にあるデレた本音、僕が世界で一番スマートに理解する（理解しています）！』って…っ！本音を理解する！バカ！/// そんな私の取扱説明書をマスターしたみたいに言うんじゃないの！…でも、あんたが私の本当の心を見抜いて寄り添ってくれるの、最高に愛おしいわ。』.
• 納得する (なっとくする (nattoku suru) - Level: N3): Maps to "to understand; to be convinced; to accept" and is used when Implies understanding and accepting something as reasonable or true after explanation or consideration. Often used in formal or serious contexts..
• 心得える (こころえる (kokoroeru) - Level: N2): Maps to "to understand, to know, to be aware of" and is used when Often used for understanding rules, manners, or proper procedures. Implies internalizing knowledge or having a good grasp of something..

Mixing these up can easily lead to unnatural translations. Refer to the bilingual context cards below to master the boundaries!