This is a much needed companion piece to our post on the same topic in Greek.  Note that many of lexical metaphors for masturbation are shared by the two languages. Much of the following material is drawn from J.N. Adams. The Latin Sexual Vocabulary. 1982. Note, however, that many of the examples are not truly masturbatory.

As an important prefatory note, the Latin word masturbor (whence modern “masturbate”) has unclear and irregular use in Latin (discussed by Adams 209-211 with some rather strong attacks on J. P. Hallet’s 1976 “Masturbator, Mascarpio.” Glotta, vol. 54: 292–308.) The word occurs most prominently in an agentive form  in Martial (translated here with considerable license):

Martial, 14.203 Puella Gaditana

“She sways with such curves and oozes sex so deep
That she’d turn Hippolytus himself into a masturbating creep.”

Tam tremulum crisat, tam blandum prurit, ut ipsum
masturbatorem fecerit Hippolytum.

Other words and terms

Frico, “to rub, chafe”, cf. cont. vulg: “rub one out”

Petronius 91.11

“it is that much more advantageous to rub your groin rather than your genius”

tanto magis expedit inguina quam ingenia fricare

Sollicito, “to shake, stir, rouse, agitate, excite, urge” etc.

Despite Adam’s assertion, the primary examples he cites are about the manipulation of genitals by another party.

Ovid, Amores 3.7.73-4

“Despite this, my girl was not reluctant
To stroke me gently once she moved her hand down…”

Hanc etiam non est mea dedignata puella
molliter admota sollicitare manu;

Martial, 11.22.4

“Who denies this? This is too much. But let it be enough
Stop urging on their groins with that fucker of a hand.”

quis negat?—hoc nimium est. sed sit satis; inguina saltem
parce fututrici sollicitare manu.

Petronius 20.2

“She stirred up my groin which was cold already because of a thousand deaths.”

Sollicitavit inguina mea mille iam mortibus frigida

Cf. Maximianus 5.58 “she began to handle my dirty parts with her hand / and to excite me too with her fingers.” contrectare manu coepit flagrantia membra / meque etiam digitis sollicitare suis

Tango, “touch”, cf. Divinyls Classic “I Touch Myself”

Ovid, Ars Amatoria 2.719–720

“When you find those places where the lady delights at being touched,
Don’t let shame get in the way of you touching her.”

Cum loca reppereris, quae tangi femina gaudet,
Non obstet, tangas quo minus illa, pudor.

Tracto: “to draw, haul, handle, treat” cf. perhaps “to jerk [off]” or “wank”

Martial 11.29.8

“I don’t need a finger: handle me like this, Phyllis”

nil opus est digitis: sic mihi, Phylli, frica

Priapea 80.1-2

“But this limp dick is not long enough nor does it stand up strong enough,
Even if you play with it, do you think it can grow?”

At non longa bene est, non stat bene mentula crassa
et quam si tractes, crescere posse putes?

Adams 1982, 208:

(de)glubo: “to skin, flay, peel” cf. “skin off”

Ausonius, Epigram 79 “Inscribed Beneath the Picture of a Lusty Lady”

Beyond the genial joining of authorized sex
Sinful lust has discovered unnatural modes of love:
What the Lemnian lack posited to the heir of Herakles,
Or what the plays of Afranius in Roman garb presented
Or the total depravity that marked the Nolan people.
Somehow, in a single body, Crispa practices all three!
She masturbates, fellates, and rides with either hole—
So that she might not die frustrated, leaving anything untried.

LXXIX.—Subscriptum Picturae Mulieris impudicae

Praeter legitimi genialia foedera coetus
repperit obscenas veneres vitiosa libido:
Herculis heredi quam Lemnia suasit egestas,
quam toga facundi scaenis agitavit Afrani
et quam Nolanis capitalis luxus inussit.
Crispa tamen cunctas exercet corpore in uno:
deglubit, fellat, molitur per utramque cavernam,
ne quid inexpertum frustra moritura relinquat.

This is a much needed companion piece to our post on the same topic in Greek.  Note that many of lexical metaphors for masturbation are shared by the two languages. Much of the following material is drawn from J.N. Adams. The Latin Sexual Vocabulary. 1982. Note, however, that many of the examples are not truly masturbatory.

As an important prefatory note, the Latin word masturbor (whence modern “masturbate”) has unclear and irregular use in Latin (discussed by Adams 209-211 with some rather strong attacks on J. P. Hallet’s 1976 “Masturbator, Mascarpio.” Glotta, vol. 54: 292–308.) The word occurs most prominently in an agentive form  in Martial (translated here with considerable license):

Martial, 14.203 Puella Gaditana

“She sways with such curves and oozes sex so deep
That she’d turn Hippolytus himself into a masturbating creep.”

Tam tremulum crisat, tam blandum prurit, ut ipsum
masturbatorem fecerit Hippolytum.

Other words and terms

Frico, “to rub, chafe”, cf. cont. vulg: “rub one out”

Petronius 91.11

“it is that much more advantageous to rub your groin rather than your genius”

tanto magis expedit inguina quam ingenia fricare

Sollicito, “to shake, stir, rouse, agitate, excite, urge” etc.

Despite Adam’s assertion, the primary examples he cites are about the manipulation of genitals by another party.

Ovid, Amores 3.7.73-4

“Despite this, my girl was not reluctant
To stroke me gently once she moved her hand down…”

Hanc etiam non est mea dedignata puella
molliter admota sollicitare manu;

Martial, 11.22.4

“Who denies this? This is too much. But let it be enough
Stop urging on their groins with that fucker of a hand.”

quis negat?—hoc nimium est. sed sit satis; inguina saltem
parce fututrici sollicitare manu.

Petronius 20.2

“She stirred up my groin which was cold already because of a thousand deaths.”

Sollicitavit inguina mea mille iam mortibus frigida

Cf. Maximianus 5.58 “she began to handle my dirty parts with her hand / and to excite me too with her fingers.” contrectare manu coepit flagrantia membra / meque etiam digitis sollicitare suis

Tango, “touch”, cf. Divinyls Classic “I Touch Myself”

Ovid, Ars Amatoria 2.719–720

“When you find those places where the lady delights at being touched,
Don’t let shame get in the way of you touching her.”

Cum loca reppereris, quae tangi femina gaudet,
Non obstet, tangas quo minus illa, pudor.

Tracto: “to draw, haul, handle, treat” cf. perhaps “to jerk [off]” or “wank”

Martial 11.29.8

“I don’t need a finger: handle me like this, Phyllis”

nil opus est digitis: sic mihi, Phylli, frica

Priapea 80.1-2

“But this limp dick is not long enough nor does it stand up strong enough,
Even if you play with it, do you think it can grow?”

At non longa bene est, non stat bene mentula crassa
et quam si tractes, crescere posse putes?

Adams 1982, 208:

(de)glubo: “to skin, flay, peel” cf. “skin off”

Ausonius, Epigram 79 “Inscribed Beneath the Picture of a Lusty Lady”

Beyond the genial joining of authorized sex
Sinful lust has discovered unnatural modes of love:
What the Lemnian lack posited to the heir of Herakles,
Or what the plays of Afranius in Roman garb presented
Or the total depravity that marked the Nolan people.
Somehow, in a single body, Crispa practices all three!
She masturbates, fellates, and rides with either hole—
So that she might not die frustrated, leaving anything untried.

LXXIX.—Subscriptum Picturae Mulieris impudicae

Praeter legitimi genialia foedera coetus
repperit obscenas veneres vitiosa libido:
Herculis heredi quam Lemnia suasit egestas,
quam toga facundi scaenis agitavit Afrani
et quam Nolanis capitalis luxus inussit.
Crispa tamen cunctas exercet corpore in uno:
deglubit, fellat, molitur per utramque cavernam,
ne quid inexpertum frustra moritura relinquat.