Causing apprehension, fear or alarm; frightening(adjective)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "alarming" in a sentence
"He also expressed concern at what he called the alarming deterioration of the public service."
""It depends on what you call alarming," the Indian said coldly."
"In the face of what she called an "alarming trend towards ever-bigger data breaches," Ms. Stoddart said she now plans to ask Industry Canada to rewrite that proposed legislation to give her the power to impose fines - powers that privacy officials have in Britain and France."