asperity

The quality of having a rough or uneven surface; roughness, unevenness; (countable, chiefly in the plural) a protruding or rough area or point on a surface; a protrusion.formaluncountable

• Oyle of ſwete Almondes and of ſiſami taketh away the aſperitie and rougheneſſe of the throte.
• The iuyce of Mynte mengled with honied water, cureth the payne of the eares being dropped therein, and taketh away the aſperitie, and roughneſſe of the tongue, whan it is rubbed or waſſhed therewith.

The quality of having a rough or uneven surface; roughness, unevenness; (countable, chiefly in the plural) a protruding or rough area or point on a surface; a protrusion.; A section of a fault line with high friction, such that there is no movement along this part of the fault except during an earthquake.countableformal

• We inferred that the locking of asperities did cause higher stresses associated with earthquake cycle itself to occur in areas adjacent to asperities, both updip and downdip from them, and that such stressing has been much less pronounced i
• Since rapid permanent plate shortening is not observed in subduction zones, there must be either strain release over a large region or strain accumulation over a small region over earthquake cycles. […] The most likely mechanism for the lat

The quality of being difficult or unpleasant to experience; (countable) a thing that is harsh and difficult to endure; a difficulty, a hardship.figurativelyformaluncountable

• the asperity of Maine’s winter

The quality of being harsh or severe in the way one behaves or speaks toward another person; (countable, chiefly in the plural) a deeply hostile or resentful feeling; an animosity, a hatred.figurativelyformaluncountable

• But leaſt he ſhoulde offend the Iewes with the aſperitie of the word, if hee had ſaid that the lawe was dead, hee vſed a digreſſion, or deflection, ſaying, we are dead to the law.
• The animadverſions of critics are commonly ſuch as may eaſily provoke the ſedateſt vvriter to ſome quickneſs of reſentment and aſperity of reply.

Of sound: gratingness, harshness.archaiccountablefiguratively

• [T]he importunate, harſh and diſharmonious Coaxations of Frogs, (ſo called in the Greek from that very ungratefull noiſe, […] from the ſhrilneſs and aſperity of the noiſe they make) […]
• [John] Miltonm therefore ſeems to have ſomevvhat miſtaken the nature of our language, of vvhich the chief defect is ruggedneſs and aſperity, and has left our harſh cadences yet harſher.

Of taste: harshness or sharpness; acridity, tartness.archaiccountablefiguratively

• [T]he aſperity of tartarous ſalts, and the fiery acrimony of alcaline ſalts, irritating and vvounding the nerves, produce naſcent paſſions and anxieties in the ſoul; vvhich both aggravate diſtempers, and render men's lives reſtleſs and vvre

Of writing: a lack of elegance and refinement; inelegance, roughness.archaiccountablefiguratively