If someone is faithless, you cannot trust them to stay true. They break a promise, a bond, or a loyalty.

If如果 someone有人 is faithless是faithless（不忠）的, you你 cannot trust them to stay true就不能相信他會維持忠誠。 They他們 break a promise, a bond, or a loyalty會打破一個承諾、一段關係，或一份忠誠。

The word is old-fashioned and heavy.

The word這個字 is old-fashioned and heavy是老派又沉重的。

You hear it most about love: a faithless husband or wife has gone to someone else. You can also use it for a friend or an ally who switches sides. It is stronger and more literary than unfaithful, which is the everyday word for cheating.

You你 hear it most about love最常聽到用在感情上: a faithless husband or wife一個faithless的丈夫或妻子 has gone to someone else是移情別戀了。 You你 can also use it for a friend or an ally也可以用在一個朋友或盟友身上 who switches sides那個轉而投靠對方的人。 It它 is stronger and more literary比unfaithful更強烈、更文言 than unfaithful, which那個字 is the everyday word for cheating才是日常說「劈腿」的字。

There is another, older reading: faithless as “having no religion.” You will meet that in poems and old books. In modern talk, though, if you call a person faithless you are almost always attacking their loyalty, not their church.

There is還有 another, older reading另一個比較舊的意思: faithless faithless可以指 as “having no religion.”「沒有宗教信仰」 You你 will meet that會在 in poems and old books詩和舊書裡遇到。 In modern talk在現代用法裡, though不過, if如果 you call a person faithless你說一個人faithless, you你 are almost always attacking their loyalty幾乎都是在指責他不忠誠, not their church而不是在說他沒有信仰。

Though actually, the hurt in the word is the broken faith — the trust that was given and then dropped. It is not a light insult, and it is not the same as “has no confidence.”

Though actually不過其實, the hurt傷害人的地方 in the word在這個字裡 is the broken faith是那份被打破的信任 — the trust那份信任 that was given and then dropped曾經被交付出去，後來卻被丟下。 It它 is not a light insult不是輕的侮辱, and而且 it它 is not the same as “has no confidence.”跟「沒自信」不是同一回事。