- attention deficit disorder (n.)
[attention deficit disorder 词源字典] - (abbreviated ADD) became a diagnosis in the third edition of the "Diagnostic and Statistical Manual of Mental Disorders" (1980); expanded to attention deficit hyperactivity disorder ("the co-existence of attentional problems and hyperactivity, with each behavior occurring infrequently alone;" ADHD) in DSM-III (1987).[attention deficit disorder etymology, attention deficit disorder origin, 英语词源]
- infrequent (adj.)
- 1530s, from Latin infrequentem (nominative infrequens) "occurring seldom, unusual; not crowded, absent," from in- "not" (see in- (1)) + frequens (see frequent). Related: Infrequently.
- swivel (n.)
- c. 1300, "coupling device that allows independent rotation," from frequentative form of stem of Old English verb swifan "to move in a course, revolve, sweep" (a class I strong verb), from Proto-Germanic *swif- (cognates: Old Frisian swiva "to be uncertain," Old Norse svifa "to rove, ramble, drift"), from PIE root *swei- (2) "to turn, bend, move in a sweeping manner."
Related Middle English swive was the principal slang verb for "to have sexual intercourse with," a sense that developed c. 1300. This probably explains why, though the root is verbal, the verb swivel is not attested in Modern English until 1794. Compare Middle English phrase smal-swivinge men "men who copulate infrequently."
