Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Perseus.
The word diarrh��a could not be parsed. Trying a normal dictionary lookup:
No entries found. Showing closest matches:
† dĭarrhoea, ae, f., = διάρ’ῤοια, diarrhœa, Cael. Aur. Acut. 3, 19.