The letter was handwritten, in a hasty, barely decipherable scrawl.

这封信是手写的，字迹潦草，几乎无法辨认。

《柯林斯英汉双解大词典》

The mark must be legible and indelible, and the characters easily decipherable.

标识应为易读且不易磨掉的，文字也应使用易理解的词语。

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The company either puts its name or decipherable initials on the back of store brands it fills.

该公司把分装商的姓名或易识别的姓名首字母加在商店品牌的后面。

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It wants the current order paper, decipherable only by parliamentary aficionados, to be replaced by a more accessible agenda.

ECONOMIST: Parliament

Adjacent to the pod is an interactive touch-screen timeline magnifying digitized exhibited documents, rendering even his nearly illegible script decipherable.

WSJ: Churchill: The Power of Words | Morgan Library & Museum | The Origins of His Oratory | by Alexander Heffner

Of the five largest ETF issuers, only three are decipherable, given that they are units of giant publicly-traded financial services firms.

FORBES: How to Make Money with ETFs