Monier-Williams: A Sanskrit-English Dictionary (p. 412)
jambu, -bU f. the rose apple tree (Eugenia jambolana or another species) Kauś. 8 MBh. &c.; the shrub nāga-damanī, L.; (-bu) n. the rose apple fruit Pāṇ. 4-3, 165; m. or f. (?; g. varaṇādi) = -dvīpa BhP. v, 1, 32; N. of a fabulous river (flowing from the mountain Meru; formed by the juice of the fruits of the immense Jambu tree on that mountain cf. MBh. vi, 277 f.) BhP. v, 20, 2; cf. āḍhaka-, kāka-, go-rakṣa-, mahā-.

Monier-Williams: A Sanskrit-English Dictionary (p. 412)
jambū, f . = -bu, the rose apple tree MBh. &c.; m. = -svāmin Jain.

Tamil Lexicon, University of Madras (p. 2236)
nāṟunaṟuvili: Clove-leaved black plum, l. tr. Eugenia jambolana caryophyllifolia

Tamil Lexicon, University of Madras (p. 2229)
nāval: 1. Jamoon-plum, l. tr., Eugenia jambolana; 2. Arnott’s mountain black plum, l. tr. Eugenia arnottiana; 3. Challenging for fight; 4. A shout of victory in the form of nāvalō - nāval; 5. A shout of joy made while heaping grain on the threshing-floor; 6. A shout of driving the oxen while treading sheaves on the threshing-floor; 7. Exclamation of grief; 8. A kind of insect which blights the gingelly crops

Dymock, Warden, Hooper: Pharmacographia Indica (vol. II, pp. 25-29)
Eugenia Jambolana, Myrtaceae
This tree, which yields an abundant crop of subacid edible fruit, during the hot weather, is common all over the country. In some places the fruit attains the size of a pigeon's egg, and is of superior quality. In Guzerat this large kind is called Pāras-jambudo. The Jambu has numerous synonyms in Sanskrit, it is called Meghavarna (cloud-coloured), Meghabha (cloud-like), Nīlaphala (black-fruited), Rājaphala (king's-fruit), &c. According to the Dirghama-Sutra it is one of the four colossal mythic trees which mark the four cardinal points, standing to the south of Mount M‚ru; four great rivers rise at its foot. The Vishnupurana states that the continent of Jambudvipa takes its name from this tree. Ibn Batuta, who visited India in 1332, mentiions Jamūn as one of the fruits of Delhi. A vinegar prepared from the juice of the ripe fruit is an agreeable stomachic and carminative; it is also used as a diuretic. A sort of spirituos liquor, called Jāmbāva, is described in recent Sanskrit works as prepared by distillation from the juice. The bark is astringent, and is used, alone or in comnination with other medicines of its class, in the preparation of stringent decoctions, gargles and washes. The fresh juice of the bark is given with goat's milk in the diarrhoea of children. (Chakradatta.) The expressed juice of the leaves is used alone or in combination with other astringents in dysentery, as for example in the following prescription: -Take of the fresh juice of the leaves of E. Jambolana and the Mango about a drachm each, Emblic myrobalans a drachm, and admioister with goat's milk and honey. (Bhavaprakasa.)
The author of the Makhzan notices the JamĹŤn at considerable length; after describing the tree, he says that the fruit is a useful astringent in bilious diarrhoea, and makes a good gargle for sore throat or lotion for ringworm of the head. The root and seeds, he observes, are useful astringents, also the leaves. He tells us that a kind of wine is made from the fruit, and that the juice of the leaves dissolves iron filings, or, as he expresses it, reduces them to so light a condition that they float upon the surface of the liquid as a scum. This when collected and washed he recommends as a tonic and astringent. A wine and syrup of the fruit has been shown to us by Mr. M. C. Pereira of Bombay; they much resemble in flavour similar preparations made with red currants, and appear to have stomachic and astringent properties. Some years ago at Monghyr, in Bengal, excellent brandy was prepared from the fermented fruit. Of late years the seeds of this tree have been recommended as a remedy in diabetes.
Dr. C. Graeser, of Bonn, has published in the Zentralblatt f r Klinische Medizin a highly-interesting account of a series of experiments with the extract of the fruit of Syzygium Jambolanum on dogs, which had previously been made diabetic by the administration of phloridzin.
Dr. Graeser thought that the best way of studying the physiological and therapeutic action of the new drug was to administer it to dogs which had artificially been made diabetic by a method introduced by V. Mehring, who found that artificial diabetes can at any moment be produced in dogs by the administration of phlorydzin.
A young dog of 2,700 to 4,800 grammes body weight, to which 2.5 to 4.8 grammes of phloridzin (1 gramme to 1 kilo body weight) have been given, in the course of a day will show an excretion of sugar, lasting for twenty-four to thirty hours, and amounting to 5.89 to 12.45 grammes. Graeser first gave the daily dose of phloridzin, but later on he split the quantity into doses of 1 gramme, given every two to three hours. In both cases the excretion of sugar was the same. Diarrhoea was caused by phloridzin in three cases. After Graeser had experimented for some time with phloridzin and extract of Syzygium Jambolanum. The latter was given before, along with, or after phloridzin, and invariably had the effect of reducing the expected excretion of sugar most considerably. This reduction amounted to at least half, in some cases even to nine-tenths, of the quantity of sugar which would have resulted had phloridzin alone been given. At the same time the duration of the diabetes was shortened. Dogs, which under phloridzin alone had excreted 5.89 to 12.45 grammes of sugar, showed under the jambul treatment a maximum excretion of 2.906 grammes of sugar, and a minimum excretion of 1.5 gramme.
As jambul showed such a powerful effect on the artificially-produced diabetes, it may be anticipated that when given at the proper time and in a large dose it will entirely prevent the excretion of sugar.
It is not yet known how jambul given in large doses acts on the pathological diabetes mellitus of man. But it is well worth trying. The experiments on man are all the more justified as no ill effect has ever yet been produced by the new drug. A favourable effect of such experiments would prove that phloridzin diabetes and pathological diabetes are of similar nature.
In all the animals on which Graeser experimented no signs of any secondary effects of jambul extract were observed, not even after doses of 18 grammes. In one case diarrhoea set in, which, as further experiments proved, was caused by phloridzin and not by jambul.
All his experiments were made with extract of jambul prepared by Mr. R.H. Davies, F.I.C., chemist to the Society of Apothecaries, London, from seeds which the author had himself brought over to Europe. As the fruit contains great quantities of starch, it was thought advisable to eliminate this as much as possible in preparing the extract. Several extracts were prepared out of the whole fruit, or solely out of the kernel or solely out of the pericarp; 100 grammes of the fruit gave 16 1/3 grammes kernel-extract, and 11 2/3 grammes pericarp extract. The most given in one single dose was 6 grammes, the maximum daily dose 18 grammes.
Whether the active principle is contained in the pericarp or kernel cannot as yet be decided to a certainity. Probably it is contained in both, but to a greater extent in the pericarp.
From the long series of experiments which he has made, Graeser draws the following conclusions:-
1. Phloridzin diabetes is considerably lessened by jambul extract.
2. Jambul extract is non-poisonous, and does not cause any ill effect.
3. The active principle contained in jambul is not yet known. It will have to be determined by careful analysis and further experiments. (Chem. and Druggist 1889.)
With reference to Graeser's experiments, G. I. Iaveine (Vratch., 1889, p. 1029), records having obtained negative results with the seeds in three cases of diabetes in which the urine contained from 6 to 7 per cent of sugar. In these cases the powdered seeds were given in doses of one gram 4 to 6 times a day.