suspenseful (adj.)

c. 1400, "abeyance, temporary cessation; state of not being carried out" (of legal matters), from Anglo-French suspens (in en suspens "in abeyance," c. 1300), Old French sospense "delay, deferment (of judgment), act of suspending," from Latin suspensus, past participle of suspendere "to hang up; interrupt" (see suspend). Meaning "state of mental uncertainty with more or less anxiety" (mid-15c.) is from legal meaning, perhaps via notion of "awaiting an expected decision," or from "state of having the mind or thoughts suspended." As a genre of novels, stories, etc., attested from 1951.