In a manner that causes intense pain, suffering, or acute distress; extremely and painfully.
The adverb form of excruciate, using the suffix -ingly to describe the manner or degree of something causing extreme pain or discomfort.
This adverb is everywhere in modern language—people say 'excruciatingly slow' or 'excruciatingly boring' to express that something is causing them real emotional pain through frustration.
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