"unintermitted continuance," 1610s, from incessant + abstract noun suffix -cy.
Entries linking to incessancy
incessant adj.
mid-15c., from Old French *incessant or directly from Late Latin incessantem (nominative incessans) "unceasing," from Latin in- "not" (see in- (1)) + cessans, present participle of cessare "to cease, go slow, give over, leave off, be idle," frequentative of cedere (past participle cessus) "go away, withdraw, yield" (from PIE root *ked- "to go, yield"). Related: Incessantly (early 15c.).
-cy
abstract noun suffix of quality or rank, from Latin -cia, -tia, from Greek -kia, -tia, from abstract ending -ia (see -ia) + stem ending -c- or -t-. The native correspondents are -ship, -hood.