suru verb (precursor), intransitive verb
Obsolete su-verb (precursor to modern suru). Used in classical or highly formal contexts; in modern Japanese, 死ぬ is the standard verb for 'to die'.
See also: 死する
古語では「死す」と書いて「しす」と読んだ。
In classical language, 死す was written and read as しす.
「死すとも自由を失わず」という碑文
An inscription remains that says, 'Even in death, I shall not lose my freedom.'
生きる means 'to live', the direct opposite of 死す's meaning 'to die'.
A サ変 verb formed from the Sino-Japanese noun 死 “death” and す, the classical form corresponding to modern する.