Adjective

(en-adj)

Urgent.

Sensitive.

Short, quick, brief.

* {{quote-magazine, year=2013, month=July-August, author= Philip J. Bushnell

, title= Solvents, Ethanol, Car Crashes & Tolerance, magazine=(American Scientist) , passage=Surprisingly, this analysis revealed that acute exposure to solvent vapors at concentrations below those associated with long-term effects appears to increase the risk of a fatal automobile accident. Furthermore, this increase in risk is comparable to the risk of death from leukemia after long-term exposure to benzene, another solvent, which has the well-known property of causing this type of cancer.}}

(geometry) Of an angle, less than 90 degrees.

(geometry) Of a triangle, having all three interior angles measuring less than 90 degrees.

(botany, of leaves) With the sides meeting directly to form a pointed acute angle at the apex, base, or both.

(medicine) Of an abnormal condition of recent or sudden onset, in contrast to delayed onset; this sense does not imply severity (unlike the common usage).

(medicine) Of a short-lived condition, in contrast to a chronic condition; this sense also does not imply severity.

* {{quote-magazine, year=2013, month=May-June, author= Katie L. Burke

, title= In the News , volume=101, issue=3, page=193, magazine=(American Scientist) , passage=Bats host many high-profile viruses that can infect humans, including severe acute respiratory syndrome and Ebola. A recent study explored the ecological variables that may contribute to bats’ propensity to harbor such zoonotic diseases by comparing them with another order of common reservoir hosts: rodents.}}

(orthography, after a letter) Having an acute accent.

High or shrill.

an acute tone or accent

Adjective

(er)

Having an acidic, sharp or tangy taste.

* Francis Bacon

All sour things, as vinegar, provoke appetite.

Made rancid by fermentation, etc.

(rfex)

Tasting or smelling rancid.

(rfex)

Peevish or bad-tempered.

* Shakespeare

He was a scholar / Lofty and sour to them that loved him not, / But to those men that sought him sweet as summer.

(of soil) Excessively acidic and thus infertile.

(of petroleum) Containing excess sulfur.

(rfex)

Unfortunate or unfavorable.

* Shakespeare

sour adversity

* {{quote-news

, year=2011 , date=October 1 , author=Phil Dawkes , title=Sunderland 2 - 2 West Brom , work=BBC Sport citation , page= , passage=The result may not quite give the Wearsiders a sweet ending to what has been a sour week, following allegations of sexual assault and drug possession against defender Titus Bramble, but it does at least demonstrate that their spirit remains strong in the face of adversity.}}