The API returns the following allegrowStatus values:

safe - Valid email that is safe to send to based on risk analysis. Includes both catch-all and non-catch-all addresses.
do_not_mail_abuse - Valid email with high risk of manual spam reports. Avoid emailing and use alternative channels like Calls and LinkedIn.
spamtrap - Valid email, but high spam trap risk. Remove contact and source new email addresses.
some_risk - Inconclusive result with identified risk factors. Remove for 30 days and re-analyze in bulk at that point.
block_bounce_risk - Invalid email highly likely to bounce. Remove contact and source new email addresses.
dead_email - Invalid account that won’t bounce due to catch-all setup. Use alternative communication channels.
more_time_required - (Sync endpoint only) More checks are still being run. Either re-try again later or upgrade to the asynchronous API to avoid this.

For a more in-depth explanation of the Allegrow statuses, please check this article.