acute angle
3 antonyms and opposites of acute angle, grouped by meaning.
Noun — An angle that measures more than 0 degrees and less than 90 degrees.
Antonyms
How to use acute angle
The word patterns that sound natural to a native speaker.
Neutral. A standard maths term taught from primary school onwards.
Etymology
From Latin acutus 'sharpened, pointed', past participle of acuere 'to sharpen'.
Full origin of acute angle →Frequently asked questions
What is the difference between an acute angle and an obtuse angle?
An acute angle is smaller than 90 degrees, so it looks sharp and narrow. An obtuse angle is greater than 90 degrees but less than 180, so it looks wide and open. A 90-degree angle itself is neither — it is a right angle.
Can a triangle have more than one acute angle?
Yes, and it must have at least two. Because the three angles add to 180 degrees, a triangle can have at most one right or obtuse angle. When all three are under 90 degrees it is called an acute triangle.
Is 90 degrees an acute angle?
No. Acute means strictly less than 90 degrees. Exactly 90 degrees is a right angle, usually marked with a small square rather than an arc.