I always get confused with benedictus. It Christian prayers, it is found both as a noun and as a (passive) verb, e.g. benedictus est. When est is omitted (not uncommon in Latin, it seems), both look identical.
This issue made me think that there might be some connection between the two forms. In particular, that the verb "produced" the noun. So, consider (non-deponent?) verbs in their third person singular passive perfect conjugation. For the verb benedico, such conjugation is benedictus est. Is the latter the etymological origin of the noun benedictus? Well, this noun means "a blessed person", this is, "someone who has been blessed" (aliguis quod benedictus est?). So there might be some sort of connection. Is this true? Is this a general rule for nouns ending in -us that are related to a verb? Other examples I have found (without trying to be exhaustive) are discursus, intellectus, loricatus, observatus.
Now, not all verbs whose passive perfect ends with -us have a related noun ending in -us. Some are close to a noun ending in -or. For instance, for the verb administro, with passive perfect administratus, there is the noun administrator. Similar with fabrico/fabricator, habito/habitator, loquor/loqutor, etc.
So, is there a connection (and perhaps a precedence) between the passive perfect conjugation and the noun for words with a common base?