The state or quality of being ascendent or in the process of rising; the condition of ascending power or influence.
From ascescent (rising, ascending) with the suffix -cy (state or condition of). A rare 19th-century formation rarely used in modern English.
Ascescency is an extremely rare word that attempts to capture a process (the act of becoming more powerful) rather than a state—modern English prefers 'ascendancy' instead.
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