In a way that is consistent, regular, and unchanging; always behaving or performing in the same manner.
From consistent (Latin consistere 'to stand together, be firm') + -ly adverbial suffix. Note: this appears to be a variant or misspelling of 'consistently'; standard modern spelling is 'consistently.'
If you see 'consisently' in old texts, it's likely a historical spelling variant, showing how even 'consistently' had alternate forms before modern standardization!
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