"something lethally dangerous" (war, the sea, dangerous machinery, etc.), 1590s, from widow (n.) + maker.
Entries linking to widow-maker
widow n.
Old English widewe, wuduwe, from Proto-Germanic *widuwō (source also of Old Saxon widowa, Old Frisian widwe, Middle Dutch, Dutch weduwe, Dutch weeuw, Old High German wituwa, German Witwe, Gothic widuwo), from PIE adjective *widhewo (source also of Sanskrit vidhuh "lonely, solitary," vidhava "widow;" Avestan vithava, Latin vidua, Old Church Slavonic vidova, Russian vdova, Old Irish fedb, Welsh guedeu "widow;" Persian beva, Greek eitheos "unmarried man;" Latin viduus "bereft, void"), from root *uidh- "to separate, divide" (see with).
Extended to "woman separated from or deserted by her husband" from mid-15c. (usually in a combination, such as grass widow). As a prefix to a name, attested from 1570s. Meaning "short line of type" (especially at the top of a column) is 1904 print shop slang. Widow's mite is from Mark xii.43. Widow's peak is from the belief that hair growing to a point on the forehead is an omen of early widowhood, suggestive of the "peak" of a widow's hood. The widow bird (1747) so-called in reference to the long black tail feathers of the males, suggestive of widows' veils.
maker n.
c. 1300, "one who creates, shapes, forms, or molds," also "God as creator," agent noun from make (v.). Specifically, "manufacturer" by late 14c. To meet (one's) maker "die" is attested by 1814.