What's the difference between slag and slaggy?

Slag

Definition:

(v. t.) The dross, or recrement, of a metal; also, vitrified cinders.
(v. t.) The scoria of a volcano.

Example Sentences:

(1) I don't want to go on slagging groups like U2 or Simple Minds that aren't worth the words.
(2) In the Netherlands both Portland cement and blast furnace cement (slags from blast furnaces with about 30% Portland cement) are used for concrete.
(3) Meanwhile the Police Federation's attempts to extract retribution for the disputed p-word, in the form of Andrew Mitchell's sacking, have been roundly slagged off by former Labour minister Chris Mullin , who last week described the organisation as "a bully", "a bunch of headbangers" and "a mighty vested interest that has seen off just about all attempts to reform the least reformed part of the public service".
(4) As Miliband prepared to deliver his speech, whose contents were trailed over the weekend in an interview with the Mail on Sunday , Boris Johnson, the Conservative mayor of London, rounded on politicians who are "slagging off" a sector that is "crucial to the British economy".
(5) Mineral wool insulation, which is made from Tennessee phosphate slag, and commonly used insulation, which is made from blast furnace slag, had similar concentrations of these radionuclides.
(6) Quantities of land-disposed or stored residuals, including slags, sludges, and dusts, are given per unit of metal production for most primary and secondary metal smelting and refining industries.
(7) However, this hazard is not associated with any index of exposure to slag wool itself.
(8) Relatively thick rock and ceramic fibres (median greater than 1 micron) induced tumours, but slag and wollastonite fibres did not, probably because of their better solubility.
(9) The radioactivity levels of coal ash and slag in Hong Kong are about the average values in other countries.
(10) The US president might be all mouth in slagging off the Russians behind their backs, but Vlad was confident he was no trousers face to face.
(11) Long-term inhalation studies using several animal species and dust preparations of fibrous glass, rock wool or slag wool have produced little evidence of pulmonary fibrosis or pulmonary tumors.
(12) Mr Cameron can hardly slag off Mr Clegg as "not fit for government" when they will have spent five years sitting in the same cabinet.
(13) Who cares?” tweeted former congressman Anthony Weiner, and slagged off Philadelphia as a “2nd tier city”: Anthony Weiner (@anthonyweiner) Honestly, who cares?
(14) Concrete blocks made with phosphate slag had enhanced 226Ra and 228Ra contents when compared to ordinary concrete block.
(15) The present study is concerned with the pulmonary pathological changes in the rats following intra-tracheal administration of sintering dust and vanadium slag separately.
(16) Now I'd love to stay and chat all night, but unfortunately I have to correct all the typos in this report, insert gags where appropriate and remove all the bits where I slagged off Steven Gerrard, who is about to lift the Champions League trophy for Liverpool.
(17) Something sticks in the throat about having the word “lad” associated with a rapist, or an abuser, or even someone who might see fit to call me a slag.
(18) 2.09pm GMT In an unusual turn of fate, the front-page headline in today’s Bild is basically “Guardian live blogger slags off German Olympic uniform”.
(19) I have lost count of the number of times I have been called a slag for refusing to accept a man's advances or to respond to street harassment.
(20) This is a band that doesn't want to be slagging off the biggest pop station in the country.