“Appoint”的英文释义为“to choose someone officially for a job or responsibility”，指由某一机构、官员或人员依据其专有权力指定某人担任某一职位，那么，此处“appointed attorney”就是指由法庭指定为无力承担律师费的被告提供代理服务的律师，也可称为“public defender”，这类律师费由政府承担，可以译为“指派律师”。

“Retain”的英文释义为“to employ a lawyer, consultant (= someone paid to give expert advice or training), etc. by paying them before you need them”，是指聘用律师或顾问。引申一下，“retainer”就是指聘用律师；律师费。那么，“retained attorney”就是指聘用的律师，不过，在我国，“委托律师”这个说法更常用。

例句1：

原文：

犯罪嫌疑人、被告人因经济困难或者其他原因没有委托辩护人的，本人及其近亲属可以向法律援助机构提出申请。对符合法律援助条件的，法律援助机构应当指派律师为其提供辩护。

犯罪嫌疑人、被告人是盲、聋、哑人，或者是尚未完全丧失辨认或者控制自己行为能力的精神病人，没有委托辩护人的，人民法院、人民检察院和公安机关应当通知法律援助机构指派律师为其提供辩护。

犯罪嫌疑人、被告人可能被判处无期徒刑、死刑，没有委托辩护人的，人民法院、人民检察院和公安机关应当通知法律援助机构指派律师为其提供辩护。

（来源：《中华人民共和国刑事诉讼法》第三十五条）

译文：

Where a criminal suspect or defendant has not retained a defender for financial hardship or other reasons, the criminal suspect or defendant or his or her close relative may file an application with a legal aid agency. If the legal aid conditions are met, the legal aid agency shall designate a lawyer to defend him or her.

Where a criminal suspect or defendant suffers vision, hearing, or speech impairment or is a mental patient who has not completely lost the ability to recognize or control his or her behavior, if he or she has not retained a defender, the people's court, people's procuratorate, and public security authority shall notify a legal aid agency to designate a lawyer to defend him or her.

Where a criminal suspect or defendant who may be sentenced to life imprisonment or death penalty has not retained a defender, the people's court, people's procuratorate, and public security authority shall notify a legal aid agency to designate a lawyer to defend him or her.

例句2：

原文：

If the attorney appointed by the U.S. magistrate judge is to continue to represent the defendant in the district court, no additional appointment by the district court should be made, except on appeal from a judgment rendered by the U.S. magistrate judge in a misdemeanor case.

译文：

如果美国治安法官指派的律师继续在地区法院代理被告，则地区法院不应另行指派律师，除非是对美国治安法官针对轻罪案件作出的判决提出上诉。

例句3：

原文：

Timely Appointment of Counsel

As noted in §210.40.10, a person financially eligible for representation should be provided with counsel as soon as feasible after being taken into custody, when first appearing before the court or U.S. magistrate judge, when formally charged, or when otherwise entitled to counsel under the CJA, whichever occurs earliest.

译文：

即时指派律师

如第210.40.10节所述，在经济方面有资格获得代理之人应在被拘留后、首次出庭或美国治安法官首次庭审、被正式指控、或根据CJA有权获得律师帮助之时（以最早发生者为准），在切实可行的情况下尽快获得律师代理。

来源：

Cambridge Dictionary；

《元照英美法词典》

https://www.uscourts.gov/rules-policies/judiciary-policies/cja-guidelines/chapter-2-ss-220-appointment-counsel