Etymology: Probably < Middle French escroe (c1270 in Old French), escroue (1392) female screw, grooved cavity in which a (male) screw revolves (French écrou nut with screw thread), probably < classical Latin scrōfa sow (see scrofula n.), perhaps via a post-classical Latin meaning ‘vulva, vagina’ (perhaps 5th cent., although none of the evidence is unequivocal). Compare (probably all ultimately < French, with medial consonant probably reflecting an earlier form in Old French): Middle Dutch schruyve (1477; Dutch schroef , earliest denoting a mechanism with a screw thread), Middle Low German schrūve screw mechanism, e.g. in a press, screw thread, screw as instrument of torture, also decorative knob or fastening in jewellery (compare sense 5b), Middle High German schrūbe (14th cent.; German Schraube ), and also (all ultimately < Middle Low German) Icelandic skrúfa (16th cent.), Old Swedish skruf (Swedish skruv ), early modern Danish skrue , skruffue (Danish skrue ), now all usually denoting a (male) screw (especially in sense 4a).Transmission into English from French seems the likeliest route on formal grounds, although if so the apparent absence of the word from Anglo-Norman is surprising. It is often argued that post-classical Latin scrofa is found in the sense ‘female screw’ in the 9th cent., but the sole example is doubtful. With the semantic development of the French word perhaps compare Spanish tuerca , †puerca nut (with screw thread), probably originally a sense development of puerca sow (compare use of classical Latin porcus (male) pig in the meaning ‘vulva, vagina’); a similar semantic development is also shown by Portuguese porca . With the later stages of the semantic development compare also German Schraubenmutter female screw, Dutch moer , †moerschroef female screw (18th cent.; showing a variant of moeder mother, with loss of the medial consonant), and the use of male and female in English. It is possible that association with classical Latin scrobis hole dug in the ground, pit, in post-classical Latin also ‘vulva, vagina’ (see scrobe n.) may have played a part in the development of the word in Latin or in Germanic languages, or both. Perhaps compare also the rare post-classical Latin form scroba sow (9th cent. in a glossarial source). The shift to normally denoting a (male) screw in English (as in other Germanic languages) probably results in large part from association with the (originally denominal) verb screw v., as do a number of the specific senses of the noun (see especially branch III.). Specific senses. With sense 12 compare screw v. 10, although this is first attested later, and sense 12 is earliest attested in the context of hunting rather than racing. However, an implicit verbal metaphor that such a horse has been screwed , i.e. broken down by some form of poor use, seems likely. (screwdriver n. 2 and screwy adj. 2 probably show secondary developments from this sense of the noun.) With sense 14 compare screw v. 15b and perhaps also sense 13.