Context: I’ve been working on scanning, having scanned about 350 lines over the past month. I’m getting about three-fourths of them right, using this web site as a criterion of correctness:
I keep having trouble with the letter “u”: vowel or consonant?
Here is a dictionary entry, with a single macron over the “e”: adsuētus. [ In case the macron doesn’t come through for you, I’ll uppercase the long “e” here: adsuEtus. ] Can I tell from this dictionary entry whether the “u” is to be read as a vowel, which makes “adsuetus” quadrisyllabic, or as a consonant, which makes it trisyllabic? Is there a convention for reading these entries?
I’m working alone, with no teacher to give timely corrections of my errors.
I don’t know what dictionary you’re looking at. A macron over the e doesn’t necessarily imply that the u is consonantal.
The (first) u in adsuetus is in fact nearly always consonantal.
Since you’re still grappling with scansion, it’s probably not much consolation to you to hear that the best guide you have to whether a letter is vocalic or consonantal is usually not a dictionary but how, in a line of verse you’re looking at, it happens to scan.
When a word like consuesco or adsuesco is used in hexametric poetry, the -u- has no choice but to be consonantal, given that the syllable before and after it are invariably long, and a sequence ¯ ˘ ¯ is not permitted.