as a noun, in biology, "genetic variant of an animal," 1955; as a verb, in cinematic special effects, c. 1987, short for metamorphosis. Related: Morphed; morphing. Earlier it was a slang shortening of morphine (1912).

1940 as one of W.H. Sheldon's three types of human bodies, from endo- + -morph, from Greek morphē "form," a word of uncertain etymology. Earlier, "a mineral encased in the crystal of another mineral" (1874). Related: Endomorphic.

"a decorative form representing a living object," 1895 (A.C. Haddon), from bio- "life" + -morph "form," from Greek morphē "form, shape; beauty, outward appearance," a word of uncertain etymology. Related: Biomorphic.

"person with a slim physique and an introverted, thoughtful personality," 1940, coined by American psychologist William H. Sheldon from ectoderm + -morph, from Greek morphē "form, shape; beauty, outward appearance," a word of uncertain etymology. So called for the embryonic ectoderm, which develops the nervous system. Related: Ectomorphic.

"person with a powerful, compact body build," 1940, from mesoderm + -morph, from Greek morphe "form, shape; beauty, outward appearance," a word of uncertain etymology. Coined by American psychologist William H. Sheldon (1898-1977); the reference is to the mesodermal layer of the embryo, from which physical structures develop. Related: Mesomorphic (attested from 1923 in chemistry, a separate coinage in reference to a state of a liquid crystal).

chief alkaloid of opium (used as a narcotic pain-killer), 1828, from French morphine or German Morphin (1816), name coined by German apothecary Friedrich Sertürner (1783-1840) in reference to Latin Morpheus (q.v.), Ovid's name for the god of dreams, from Greek morphē "form, shape, beauty, outward appearance," which is of unknown origin. So called because of the drug's sleep-inducing properties.

in biology, "of or pertaining to form," 1826, from Greek morphē "form, shape," a word of uncertain etymology, + -ic.

"mad craving for morphine," 1885; see morphine + mania. Other words in the same sense were morphinism (1875, after German Morphiumsucht); morphiomania (1876). Related: Morphinomaniac; morphiomaniac.

"smallest meaningful unit in a language," 1896 (but originally in a different sense, "root, suffix, prefix, etc."), from German morpheme, coined 1895 by Polish-born linguist Jan Baudouin de Courtenay (1845-1929), from Greek morphē "form, shape," a word of uncertain etymology, on analogy of phonème.

1863 in biology, "the production of the form or shape of an organism," from German (by 1844); see  morpho- "form" + -genesis "birth, origin, creation." By 1958 in geology, "the formation of landscapes." Related: Morphogenetic.