In a way that suggests secret plotting or agreement to do something unlawful; in a manner suggesting conspiracy.
From 'conspiring' (from Latin 'conspirare': to breathe together), from 'com-' (together) + 'spirare' (to breathe), + adverbial '-ly'. The root literally means 'breathing together'.
The Latin root 'spirare' (breathe) gives us conspiracy, respiration, and inspiration—all about shared breath or spirit, which is poetic for 'people secretly united in purpose'.
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