economical

Compared meaning: saving money, time, or effort; efficient (adjective).

比较义项：形容某事物划算、省钱或高效，不浪费金钱、时间或步骤（形容词）。

• economic

  Describes a decision, plan, or venture as making financial sense given its costs and benefits, often in business contexts like 'not economic to repair'; distinct from economical, which describes ongoing frugal spending or resource use.

  形容某项决策、计划或投资从成本收益角度来看是否 economic（划算），常用于商业语境；这与形容长期省钱、节省资源习惯的 economical 不同。

  Opening a new store in that small town simply wasn't economic.

  在那个小镇开一家新店，从成本收益角度来看根本不 economic。

• efficient

  Focuses on completing a task well while wasting little time or effort, and can describe people, machines, or processes; unlike economic or economical, it does not primarily concern money.

  强调完成任务时不浪费时间或精力，可以形容人、机器或流程是否 efficient（高效）；与 economic、economical 不同，它主要不涉及金钱。

  The new dishwasher is efficient, finishing a full load in under an hour.

  这台新洗碗机很 efficient，不到一小时就能洗完满满一盆碗。

• economical 本词

  Describes ongoing good value for money, especially the running costs of vehicles or appliances, or a person's careful spending habits; contrasts with economic, which usually describes a single decision or venture.

  形容长期使用中是否划算，尤指车辆、电器的使用成本，或一个人省钱的习惯，是否 economical；这与通常形容单次决策或投资的 economic 不同。

  Her little hatchback is economical, costing very little to run every month.

  她那辆小掀背车很 economical，每个月的使用成本非常低。

• streamlined

  Describes a process, system, or design that has been simplified by removing unnecessary steps, so it works smoothly and quickly; emphasizes the act of simplifying, not just good performance or low cost.

  形容某个流程、系统或设计经过简化、去掉了多余的步骤，因而运作顺畅快捷，是否 streamlined；强调“简化”这一过程本身，而不只是表现好或成本低。

  The company adopted a streamlined checkout process, cutting the steps from six to two.

  这家公司采用了 streamlined 的结账流程，把步骤从六步精简到两步。

All four describe saving money, time, or effort. Economic describes whether a decision or plan makes financial sense. Economical describes ongoing good value, like a car's running costs. Efficient means wasting little time or effort. Streamlined means a process was simplified by removing extra steps.

这四个词都可以表示“划算、省钱或高效”，但语气和适用对象不同：economic 常用于形容一项决策、计划或投资在经济上是否合算；economical 常用于形容产品或个人用钱习惯是否长期省钱；efficient 强调做事不浪费时间和精力，不一定涉及金钱；streamlined 强调流程或设计被简化、去掉了多余步骤。这里不比较 economic“与经济有关的”这一更常见义项（如 economic policy），也不比较 streamlined 字面上“流线型（外形）”的意思。