Online Etymology Dictionary

mammal: 1826, Anglicized form of Mod.L. Mammalia (1773), coined 1758 by Linnaeus for the class of mammals, from neut. pl. of L.L. mammalis "of the breast," from L. mamma "breast," perhaps cognate with mamma.
wombat: marsupial mammal of Australia, 1798, from aboriginal Australian womback, wombar.
panda: 1835, from Fr., apparently from Nepalese name of a raccoon-like mammal (lesser panda) found there. First reference to the Giant Panda is from 1901; since its discovers in 1869 by Fr. missionary Armand David (1826-1900) it had been known as parti-colored bear, but the name was changed after the zoological relationship to the red panda was established.
pangolin: 1774, "scaly toothless mammal of Java," from Malay peng-goling "roller," from its habit of curling into a ball; from peng- (denominative prefix) + goling "to roll." Later extended to related species in Asia and Africa.
wolverine: carnivorous mammal, 1619, alteration of wolvering (1574), of uncertain origin, possibly from wolv-, inflectional stem of wolf, or perhaps from wolver "one who behaves like a wolf" (1593).
lemur: "nocturnal Madagascar mammal," 1795, coined by Linnaeus, from L. lemures (pl.) "spirits of the dead" in Roman mythology. So called for its nocturnal habits and ghostly stares. Lemuria (1864) was the name given by P.L. Sclater to a hypothetical ancient continent connecting Africa and Southeastern Asia (and including Madagascar), which was hypothesized to explain phenomena now accounted for by continental drift.
sucker: "young mammal before it is weaned," 1382, from suck. Slang meaning "person who is easily deceived" is first attested 1836, Amer.Eng., on notion of naivete; the verb in this sense is from 1939. But another theory traces the slang meaning to the fish called a sucker (1753), on the notion of being easy to catch in their annual migrations. Meaning "lollipop" is from 1823. Suckerpunch first recorded 1947.
seal (n.2): "mammal with flippers," O.E. seolh "seal," from P.Gmc. *selkhaz (cf. O.N. selr, Swed. sjöl, M.L.G. sel, M.Du. seel, O.H.G. selah), of unknown origin, perhaps a borrowing from Finnic.
sloth: c.1175, "indolence, sluggishness," formed from M.E. slou, slowe (see slow); replacing O.E. slæwð. Sense of "slowness, tardiness" is from c.1380. As one of the deadly sins, it translates L. accidia. The slow-moving mammal first so called 1613, a translation of Port. preguiça, from L. pigritia "laziness" (cf. Sp. perezosa "slothful," also "the sloth").
echidna: Australian egg-laying hedgehog-like mammal, 1847, usually explained as from Gk. ekhidna "snake, viper," from ekhis "snake," from PIE *angwhi- "snake, eel." But this sense is difficult to reconcile (unless it is a reference to the ant-eating tongue), and it seems more properly to belong to L. echinus, Gk. ekhinos "hedgehog" (in Gk. also "sea-urchin"), which Watkins explains as "snake-eater," from ekhis "snake."
antelope: lealy 15c., from O.Fr. antelop, from M.L. ant(h)alopus, from Gk. antholops (attested in Eusebius of Antioch, c.336 C.E.), a fabulous animal haunting the banks of the Euphrates, very savage, hard to catch and having long saw-like horns capable of cutting down trees. Original sense and language unknown (it looks like Gk. "flower-eye," as if from anthos + ops, but that may be a result of Gk. folk etymology). A heraldic animal, also known in M.L. as talopus and calopus, the name was applied in 1607 to a living type of deer-like mammal. In the western U.S., used in ref. to the pronghorn.
sable (1): 1423, from M.Fr. sable (also martre sable "sable martin"), in reference to the mammal or its fur, from O.Fr., from a Gmc. source (cf. M.Du. sabel, M.L.G. sabel, M.H.G. zobel), ultimately from a Slavic source (cf. Rus., Pol., Czech sobol, the name of the animal), "which itself is borrowed from an East-Asiatic language" [Klein].
dragon: early 13c., from O.Fr. dragon, from L. draconem (nom. draco) "serpent, dragon," from Gk. drakon (gen. drakontos) "serpent, seafish," from drak-, strong aorist stem of derkesthai "to see clearly." But perhaps the lit. sense is "the one with the (deadly) glance." The young are dragonets (14c.). Obsolete drake "dragon" is an older borrowing of the same word. Used in the Bible to translate Heb. tannin "a great sea-monster," and tan, a desert mammal now believed to be the jackal.
mole (2): "burrowing mammal," late 14c., probably from obsolete mouldwarp, lit. "earth-thrower" (common Gmc., cf. O.S. moldwerp, O.H.G. multwurf), from to O.E. molde "earth, soil" (see mold (3)) + weorpan "to throw away" (see warp). Spy sense first recorded 1974 in John le Carré, from notion of "burrowing." Metaphoric use for "one who works in darkness" is from c.1600.
"To much amplifying thinges yt. be but small, makyng mountaines of Molehils." [John Foxe, "Acts and Monuments," 1570]
shrew: "small mammal," O.E. screawa "shrew-mouse," unknown outside English, perhaps from P.Gmc. *skreu- "to cut" (see shred). Alternative O.E. word for it was scirfemus, from sceorfan "to gnaw." The meaning "peevish, malignant, clamorous, spiteful, vexatious, turbulent woman" [Johnson] is late 14c., from earlier sense of "spiteful person" (male or female), mid-13c., traditionally said to derive from some supposed malignant influence of the animal, which was once believed to have a venomous bite and was held in superstitious dread. Shrewish "scolding" is from 1560s, originally "wicked, evil" (late 14c.).
bat (n.2): "flying mammal" (order Chiroptera), 1570s, a dialect alteration of M.E. bakke, which is probably related to O.Swed. natbakka, O.Dan. nathbakkæ "night bat," and O.N. leðrblaka "leather flapper," so original sense is likely "flapper." The shift from -k- to -t- may have come through confusion of bakke with L. blatta "moth, nocturnal insect." O.E. word for the animal was hreremus, from hreran "to shake." As a contemptuous term for an old woman, perhaps a suggestion of witchcraft (cf. fly-by-night), or from bat as "prostitute who plies her trade by night" [Farmer, who calls it "old slang" and finds Fr. equivalent "night swallow" (hirondelle de nuit) "more poetic"].