Are there other verbs in -uō?

Question

Someone asked me recently about the conjugation of the obscene verb futuō, futuere, futuī, futūtus—and in particular about the quantity of the ū in the participle.

I intended to look at some other -uō verbs to compare them, but realized I couldn't think of any others off the top of my head. The only one that came to mind was renuō, which is intransitive and doesn't have a passive participle. (L&S don't list a future participle either, which I'm taking to mean that form is unattested.)

Are there other verbs in -uō? And if so, do they have participles in -ūtus? (Intransitive verbs with participles in -ūturus are also welcome!)

Answer 1

There is abluō, abluere, abluī, ablūtus.

And acuō, acuere, acuī, acūtus.

And arguō, arguere, arguī, argūtus.

And compluō, compluere, compluī, complūtus.

And exuō, exuere, exuī, exūtus.

And futuō, futuere, futuī, futūtus.

And imbuō, imbuere, imbuī, imbūtus.

And minuō, minuere, minuī, minūtus.

And rŭo, ruere, rŭi, rŭtus.

And spŭo, spuere, spui, spūtus.

And statuō, statuere, statuī, statūtus.

And suō, suere, suī, sūtus.

And tribuō, tribuere, tribuī, tribūtus.

Note that some/many future participles of the above verbs go -uitūrus rather than -uturus.

If you will accept volvo, voluere, volvi, volutus, considering that u/v was one letter in Latin script (though not sound), perhaps vŏlūtus will do? At least the participle has a real, vocalic u.

The participle locūtus/loquūtus could also be interesting, if you will accept a verb with first person singular present -quo-. (loquor).

The same applies to sĕcūtus from sequor.

Those are all participles on -utus that I could find. So the only participle with a short -ŭ- is rŭo. I wonder why!

Answer 2

Szemerényi (1980) says that the following "descriptive rule" summarizes the conjugation pattern for verbs ending in -uo:

verbs in -uo in general form their perfect in -uī, their PPP in -ūtus (even tuor/tūtus would conform to this rule!); a list would have to specify four exceptions: ruo has rūtus, but in the compounds -rŭtus; two verbs which have a velar in the perfect (fluxī, struxī) show it in the PPP, too, as does frūctus from fruor.

(pp. 11-12)

I was a bit confused by the rule saying that the length of the vowel in -rutus depends on whether the word is a compound. The explanation actually seems to be that there are two different verbs that have ruo as the first principal part. Szemerényi refers to them as ¹ruo and ²ruo. For more details, see my answer to the related question "Why is there a short ŭ in rŭtus?"

Lists of verbs

On p. 11, before giving the rule that I quoted earlier in this answer, Szemerényi lists and categorizes the verbs:

2.1. [...]
(a) A small group has no forms for the PPP and in some cases not even for the perfect. Here belong:

battuo      -ere     -uī     --
¹cluo       -ere     --      --
²cluo       -ere     --      --
(con)gruo   -ere     -uī     --
gruo        -ere     --      --   
pluit       -ere    -uit     --  
sternuo     -ere    -uit     --  

(b) The great majority – fifteen verbs – show -uī and -ūtum in these forms. They are: acuo, arguo, futuo, imbuo, induo, (ē)luo, metuo, minuo, nuo, polluo, ²ruo, spuo, statuo, suo, tribuo. We should perhaps add here dēlibūtus, and certainly also ²luo as shown by solūtum (see fn. 2).

(c) Two verbs deviate from this main type in that they show -ŭtum. One of them is attested in Classical times: ¹ruo-rutum. For the other, ¹cluo, the form clutus is indirectly attested by inclutus 'famous'.

(d) Two other verbs show in the perfect and the PPP a velar stem:

fluo       -ere     fluxī      fluctum (later fluxus)
struo      -ere     struxī     structum.

No doubt (see also 3.1 (8) further down) the same type is seen in

fruor      fruī     frūctus;

the form frūctus was the norm in Classical times, fruitus is a later innovation, perhaps preceded by fruitūrus (Cicero).

The same formation as in fruitus is seen in tuitus, which again seems later than tūtus.

Although Szemerényi doesn't seem to mention it, the supine of ¹ruo likewise seems to have had the variant form ruitum at some point.

There is more discussion of the forms and their probable development in the paper. Unfortunately, I can't really summarize it (partly because it is very detailed, and partly because I haven't been able to read it through yet because I've only accessed it through Google Books).

But at the end, there is a categorization of the verbs according to etymology and a passage that seems to explain the long vowel in the ending -ūtus for many of the verbs:

3.2. On the strength of our findings in 3.1, we can group the twenty-nine verbs in -uo according to the original formations as follows:

(a) thematic root-formations (-ewō, one instance -owō): ²cluo, ¹luo, pluit, ¹ruo, struo;
(b) thematized nasal-infix formation: sternuo;
(c) primary -yo: induo (*end-au-yō); fluo (*bhleug-yō); fruor (*bhrūg-yō-r); ¹gruo (*grū-yō, or gruwō?); ²gruo (*grū-yō, or gru-it?); ²luo (*lū̆-yō); polluo (*³lŭ-yō, or *lowō?); ²ruo (*rū-yō); spuo (*spyū-yō); suo (*syū-yō);
(d) denominative -yo: acuo, arguo, futuo, metuo, minuo, statuo, tribuo (all -ŭyō or -ūyō?);
(e) pairs of basic verb and intensive (cf. σπένδω: spondeo; *tendo, tondeo):
nuo : nueo (*newō : *noweyō)
tuor : tueor (*tewōr : *toweyōr)
?cluo : clueo (*klewō : *kloweyō? but rather late innovation ¹cluo beside old clueo);
(f): of obscure structure: battuo, dēlibūtus, imbuo.

4. The PPP has, as we have seen (2.1), -ūtus in the denominatives. This is what we should expect in any case, seeing that before the suffix -to the stem-final vowel is lengthened even in purely adjectival forms; c.f. aurītus, crīnītus, turrītus, on the one hand, argūtus, cinctūtus, cornūtus, versūtus, verūtus, on the other, and, outside Italy, e.g., Greek δακρῡτός 'wept over, tearful'.

(p. 28)

Works cited

Szemerényi, Oswald. 1980. "Latin Verbs in uo, uere". Italic and Romance Linguistic Studies in Honor of Ernst Pulgram, edited by Herbert J. Izzo.

De Vaan, Michiel. 2008. Etymological Dictionary of Latin and the Other Italic Languages.