acute
UK[əˈkjuːt]US[əˈkjuːt]
adj
(of a bad, difficult, or unwelcome situation or phenomenon) present or experienced to a severe or intense degree.
adj
having or showing a perceptive understanding or insight; shrewd.
adj
(of an angle) less than 90°.
adj
(of a disease or its symptoms) severe but of short duration.
Etymology
the word 'acute' entered english in the late 14th century from the latin 'acutus', the past participle of 'acuere', meaning 'to sharpen'. this latin verb itself is derived from the proto-indo-european root ak-, meaning 'sharp' or 'pointed'. the semantic journey from the literal 'sharpened' to the modern abstract meanings is clear: a sharp point leads to intensity (acute pain), a sharp mind leads to perceptiveness (acute observation), and a sharp angle is one that is narrow and less than 90 degrees. the medical sense of a severe but short-lived illness also carries the connotation of a sharp, intense onset.
Analysis
the word 'acute' is a simplex loanword from latin. it does not contain separable morphemes within its modern english spelling.
Examples
the region is facing an acute shortage of clean water.
her acute business sense allowed her to anticipate the market shift.
in a right triangle, one of the non-right angles is always acute.