Webster’s Revised Unabridged Dictionary · 1913
Lysis
Ly′sis (lī′sĭs), n. [NL., fr. Gr. λύσις.] (Med.) The resolution or favorable termination of a disease, coming on gradually and not marked by abrupt change.
☞ It is usually contrasted with crisis, in which the improvement is sudden and marked; as, pneumonia ends by crisis, typhoid fever by lysis.