Webster's Revised Unabridged Dictionary · 1913

Dangerous

Dangerous , adjective

[Old English, haughty, difficult, dangerous, from Old French dangereus, French dangereux. See Danger.]

1.
Attended or beset with danger; full of risk; perilous; hazardous; unsafe.
Our troops set forth to-morrow; stay with us; The ways are dangerous. — Shakespeare
It is dangerous to assert a negative. — Macaulay
2.
Causing danger; ready to do harm or injury.
If they incline to think you dangerous To less than gods. — Milton
3.
In a condition of danger, as from illness; threatened with death. [Colloquial] — Forby. Bartlett
4.
Hard to suit; difficult to please. [Obsolete]
My wages ben full strait, and eke full small; My lord to me is hard and dangerous. — Chaucer
5.
Reserved; not affable. [Obsolete]
Of his speech dangerous. — Chaucer