epoch

Compared meaning: a long period marked by certain features (noun).

比较义项：时代，以特定事件或特征为标志的一段较长时期（名词）。

• era

  The common, everyday word for a long period marked by certain features or events; neutral in tone and used in both casual and formal speech.

  era 是描述以某些特征或事件为标志的一段较长时期的常用词，语气中性，日常和正式场合都可以使用。

  Smartphones changed our lives and started a new era.

  智能手机改变了我们的生活，开创了一个新时代。

• epoch 本词

  A more formal, often scientific or historical word, usually marking the beginning or a turning point of a period rather than the period's everyday feel.

  epoch 是更正式、常用于科学或历史语境的词，通常强调某一时期的开端或转折点，而不是描述日常生活中笼统的一段时期。

  Geologists say a new epoch began when the last ice age ended.

  地质学家说，上一次冰河时代结束后，一个新纪元开始了。

Era and epoch both mean a long period marked by certain features. Era is the common, everyday word, neutral in tone, used in both casual and formal speech. Epoch is more formal, often scientific or historical, marking the start or a turning point.

era 和 epoch 在这个意义上很接近，都指“时代”，但语气不同：era 是日常常用词，epoch 更正式、更书面，常用于历史或科学语境，强调某一时期的开端或转折点。