According to lengthy reports carried in US newspapers, Ms Lewinsky was asked very specific questions about the nature of her relationship with Mr Clinton and about what she did with presents he had given her. These are two points on which her original testimony two weeks before and Mr Clinton's testimony on Monday are widely reported to differ.
The preciseness of yesterday's reports contrasted with the sketchy accounts of her testimony two weeks earlier, when the main information conveyed was that she had admitted to "a certain sort of sex" with the President, subsequently clarified as oral sex. This fact was reported to have been implicitly confirmed by Mr Clinton under questioning on Monday.
Recalled before the grand jury on Thursday, Ms Lewinsky apparently gave prosecutors the potentially damaging information that the President touched and fondled her breasts and genitals.
The significance of these disclosures is that such contact would come unambiguously under the definition of sexual relations used by lawyers in the Paula Jones sexual harassment case in January, the occasion on which Mr Clinton categorically denied having sexual relations with Ms Lewinsky. In his televised statement after giving testimony last Monday, Mr Clinton said that while he had not "volunteered information", his answers to Ms Jones's lawyers had been "legally accurate".
The definition of "sexual relations", according to the edited transcript of his evidence then, was "when the person knowingly engages in or causes ... contact with the genitalia, anus, groin, breast, inner thigh, or buttocks of any person with an intent to arouse or gratify the sexual desire of any person".
This gave him the technical opportunity to deny the relationship if the main activity was oral sex and she was the one active participant - which he did. If, however, he did touch and fondle her as she apparently described, his denial of "sexual relations" according to the agreed definition may not have been "legally accurate", leaving him open to the accusation of perjury.
The other line of questioning described yesterday relates to presents that Mr Clinton agrees he gave to Ms Lewinsky. She reportedly confirmed that Mr Clinton's personal secretary, Betty Currie, came to her flat, saying she believed Ms Lewinsky had "some things" for her.
No one denies the presents ended up with Ms Currie. What is contested is whether he instigated their transfer, or whether Ms Lewinsky arranged the transfer unprompted. Any prompting from Mr Clinton could help to substantiate the accusation that he tried to obstruct the course of justice by concealing evidence.
In his televised admission on Monday night, he said he had told the grand jury "and I say to you now, that at no time did I ask anyone to lie, to hide or destroy evidence or to take any other unlawful action". If he engineered the removal of the presents, which were then subject to subpoena as evidence in the Paula Jones case, this was illegal.
Before attending the courthouse on Thursday - a four-hour appearance that was thoroughly eclipsed by the end of the day by US military action in Sudan and Afghanistan - Ms Lewinsky had let the American media know of her unhappiness with Mr Clinton's admission. The gamut of US newspapers carried comments attributed to "friends" of hers, saying that she was "hurt" and "angered", in particular by the absence of any apology to her, or her family, and by the implication that the almost two-year relationship was merely a matter of "sexual servicing". She has insisted throughout that there was an emotional and psychological bond between them.Reuse content