legitimate

Compared meaning: allowed or recognized by law (adjective).

比较义项：合法的（形容词）。

• legitimate 本词

  Describes something (a reason, claim, or action) that is valid and acceptable under law or accepted rules; neutral, everyday register, often paired with abstract nouns like reason, concern, or claim.

  形容某事（理由、要求、行为等）在法律或公认规则下是有效、可接受的；语域中性、日常，常与 reason（理由）、concern（担忧）、claim（主张）等抽象名词搭配。

  He raised a legitimate concern that no one had thought of before.

  他提出了一个此前没人想到的合理担忧。

• rightful

  Describes someone's legal or moral entitlement to a specific person, thing, or position; typically modifies nouns like owner, heir, or place, emphasizing that this person deserves or is entitled to it.

  指某人在法律或道德上对某个人、某物或某个位置拥有应得的权利；常用于修饰 owner（所有者）、heir（继承人）、place（位置）等名词，强调这个人理应拥有或占据它。

  The court ruled she was the rightful owner of the house.

  法院裁定她是这栋房子的合法所有者。

• lawful

  Formal register meaning permitted or recognized by law; often used for official actions, orders, or regulations (a lawful order, lawful authority), focusing on compliance with the law itself rather than fairness.

  语域正式，指被法律允许或认可；常用于官方行为、命令或规定（lawful order 合法命令、lawful authority 合法权力），侧重于是否符合法律本身，而不是是否公平。

  Police officers must obey a lawful order from their superior.

  警察必须服从上级下达的合法命令。

Legitimate, rightful, and lawful all mean allowed by law, but differ: legitimate describes a reason, claim, or action that is valid and accepted. Rightful describes someone's legal or moral right to a person, thing, or position. Lawful is formal, used for official actions and orders.

这三个词在“合法的”这一意义上很接近，但侧重点不同：legitimate 强调理由、要求等被普遍认为合理正当；rightful 强调对某人、某物拥有法律或道德上应有的权利；lawful 语气更正式，多用于法律、规章等官方场合，强调符合法律规定。

Compared meaning: reasonable, well-founded (adjective).

比较义项：合理的、有根据的（形容词）。

• sound

  Describes judgment, advice, or reasoning that is solid, well-founded, and free of flaws, based on experience or good sense; typically pairs with advice, investment, or judgment.

  形容判断、建议或推理稳妥、有根据、没有漏洞，通常基于经验或良好的判断力，常见于建议、投资、判断等场合。

  Her financial advisor gave her sound advice about saving for retirement.

  她的理财顾问就退休储蓄给了她合理稳妥的建议。

• legitimate 本词

  Describes a reason, concern, or complaint that is fair and justified, often used to defend it against being dismissed or doubted by others.

  形容理由、担忧或抱怨公平合理，令人信服，常用于为其辩护，以防被别人忽视或质疑。

  Employees voiced a legitimate complaint about the unsafe working conditions.

  员工们就不安全的工作条件提出了合理正当的抱怨。

• valid

  Describes an argument or objection that follows logically and holds up under scrutiny, focusing on whether the reasoning itself is correct.

  形容论点或异议在逻辑上站得住脚、经得起推敲，重点在于推理本身是否正确。

  She raised a valid objection to the flawed research methodology.

  她针对存在缺陷的研究方法提出了一个站得住脚的合理异议。

• reasoned

  Describes a decision or response that is careful and logical because the person thought it through step by step, contrasted with an emotional or hasty reaction.

  形容决定或回应经过深思熟虑、有条理，因为当事人一步步推理过，与情绪化或仓促的反应相对。

  He gave a reasoned response instead of reacting in anger.

  他给出了一个经过深思熟虑的合理回应，而不是愤怒地做出反应。

Sound, legitimate, valid, and reasoned all describe something well-founded, but differ: sound describes solid, reliable judgment or advice. Legitimate describes a reason that is fair and justified. Valid describes an argument that follows logically and holds up. Reasoned describes a decision made carefully and logically.

这几个词在“合理、有根据”这一义项上意思相近，但语气和使用场合不同：sound 强调判断或建议稳妥可靠，legitimate 强调理由或诉求正当、值得认可，valid 强调论点在逻辑上站得住脚，reasoned 强调经过深思熟虑、有条理。这里不比较 sound 的“声音”或“健康的”义，不比较 legitimate 的“合法的”义，也不比较 valid 的“有效的”（如护照、车票仍然有效）义。