A Grammar of Tamashek (Tuareg of Mali)

8.3 Mediopassive Al 3

We get exceptional -η- for expected -m- in a handful of frozen and
semantically specialized "mediopassive" stems whose (apparent) input has no
labial C. This appears to be the case in -n-vktu- (PerfP -ann-akta-) 'do by
habit', cf. -vktu- 'remember'; in -n-ilvs- (PerfP -aen-elass-) 'be repeated'
(A-grm PerfP -ann-elaes-), cf. -dvs- 'repeat'; and in -n-vwvl- (Imprt n-sewael)
'take a walk, stroll', cf. -vwvl- 'turn around'.
The MAN stem paradigm of mediopassives of input light verb stems that
lack full vowels is illustrated in (483).

(483) Mediopassive Inflection for -vPQvC- and -vCvC- Stems

-vPQvC-

'be mixed'

-m-vrtvy-

-vCvC-

'be (all) bitten'

-m-vdvd-

a. perfective system

PerfP

Resit

PerfN

-amm-artaey-

-amm-irtaey-

-amm-artaey-

-amm-adaed-

-amm-ldaed-

-amm-adaed-

b. short imperfective system

Shlmpf -semm-asrtasy- -aemm-aedaed-

Imprt m-aertaey m-aedaed

c. long imperfective system

LoImpfP

LoImpfN

Prohib

-t-am-asrtay-

-t-am-artiy-

t-aem-aertay-

-t-am-aedad-

-t-am-adid-

-t-£em-aedad-

d. nominalizations

VblN a-m-artay a-m-adad

Another example of -vPQvC- input is -vgkvd- 'cut', mediopassive
-m-vqkvd- (PerfP -amm-aqkasd-).
Since -vPPvC- verbs in causative and other derivatives show a
reconfigured input stem variant -uPvC-, one wonders whether the
mediopassive of -vPPvC- would take the transparent form -m-vPPvC-
(-n-vPPvC-) or the reconfigured form -m-uPvC- (-n-uPvC-). If -mvzzvy-
'become divorced' is connected with -vzzvy- 'get well, recover from illness',
in addition to embodying a worldly-wise philosophy of human relationships it
also provides an instance of the hypothesized -m-vPPvC- mediopassive shape.
MGT 7.93 gives (from Foucauld) Algerian Imprt "mukkas" as reflexive (i.e.
mediopassive) of -vkkvs- 'take away', showing both the full V (here u) and
the geminate, while LTF2 169 has Imprt "mäkkäs" with shortened V for Niger
(Tawellemmett dialect).