What word can I use besides "hallmark"? As in,"A hallmark of the disorder is impaired..." Are there any synonyms that give emphasis like hallmark? Perhaps "trademark", but can a disorder have a trademark?
Why use a different word? Hallmark works, so go with it. Trademark, by the way, doesn't sound like an appropriate synonym based on the context of your sentence.
characteristic symptom, distinguishing characteristic, signature feature. If one word is inadequte, use two. But what is wrong with "hallmark"?
if discussing a 'condition' i wouldn't consider 'hallmark' the most reader-friendly word to use in referring to a 'symptom'... though its definition of 'distinguishing feature or characteristic' would certainly make your sentence clearly understood... other good alternatives: telltale/sure sign indication mark indicator aspect attribute ...plus many more you can find in any thesaurus...
Wow, you guys have been SO helpful! I just didn't want to use that term because the author of the study I am referencing uses that word often...and I feel uncomfortable with "stealing" it. I guess I was just looking to see if there were other options. I think "distinguishing characteristic" works well. Thank you!