Dangerous means able to hurt you — a dangerous road, a dangerous animal, a dangerous idea. It is the everyday word and it covers physical harm and every other kind.
The construction to watch is dangerous for versus dangerous to: dangerous for children means they are at risk, dangerous to handle means the handling is the risky part. Both are common. Note the family, because it is irregular in an unexpected way: the noun is danger, and the verb is endanger, not danger. And in danger of is the standard pattern for something bad that may happen: in danger of losing his job.
1adjectivedangerousAble to cause harm or injury.~86%
“That corner is dangerous in the wet.”
2adjectiveseriousLikely to cause serious trouble.~14%
“It is a dangerous thing to promise before you have checked.”
Shares are an estimate: a language model read 7 sentences found in the wild and placed 7 of them on a sense — a count of our sample, not a measurement of English.
dangerous is a quality of risk.
Old French dangereus first meant domineering or difficult, from a word for the power a lord held over you — his danger. The sense of physical risk came later; the original was about being in somebody's power, which is a different and older kind of fear.
Old French
dangereus — threatening, difficult
Middle English
daungerous — difficult, severe, domineering, arrogant, fraught with danger
English, today
dangerous
From Middle English daungerous (“difficult, severe, domineering, arrogant, fraught with danger”), dangerous, from Anglo-Norman, from Old French dangereus (“threatening, difficult”), from dangier. Equivalent to danger + -ous. Displaced native Old English frēcne.
Etymology from Wiktionary, CC BY-SA