Anxious means troubled by constant worry about what might go wrong. The mind running ahead to the worst version.
It takes about for the worry: anxious about the results, anxious about money. There is a second sense that means eager, as in anxious to help or anxious to please, and there the worry is only about not managing it. Medicine uses the word precisely, since anxiety is a diagnosable condition and not merely a mood. Nervous is the everyday word, and worried is the plainest of the three.
1adjectiveanxiousWorried and uneasy about what may happen.
“She was anxious about the operation.”
2adjectiveeagerEager and impatient to do something.
“He was anxious to make a good impression.”
Too few real examples of this word to estimate which sense is commonest.
Anxious is a tightness in the throat. Latin angō meant to choke or to cause pain, and the same root stands behind anger and angst, so anxiety was a narrowing before it was a mood.
Proto-Indo-European
*h₂enǵʰ-
Latin
ānxius
English, today
anxious
Built from
Borrowed from Latin ānxius. Latin anxius, from angō (“to cause pain, choke”); akin to Ancient Greek ἄγχω (“to choke”). See anger; angst.
Etymology from Wiktionary, CC BY-SA