simile

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A figure of speech in which two essentially unlike things are compared, often in a phrase introduced by like or as, as in “How like the winter hath my absence been” or “So are you to my thoughts as food to life” (Shakespeare).

from The Century Dictionary.

• noun In rhetoric, the comparing or likening of two things having some strong point or points of resemblance, both of which are mentioned and the comparison directly stated; a poetic or imaginative comparison; also, the verbal expression or embodiment of such a comparison.
• noun Synonyms Simile, Metaphor, Comparison, Allegory, Parable, Fable, similitude, trope. The first six words agree in implying or expressing likeness between a main person or thing and a subordinate one. Simile is a statement of the likeness in literal terms: as, man is like grass; Herod is like a fox. Metaphor taxes the imagination by saying that the first object is the second, or by speaking as though it were; as, “All flesh is grass,” Isa, xl. 6; “Go ye and tell that fox,” Luke xiii. 32. There are various combinations of simile and metaphor: as, “We all do fade as a leaf,” Isa. lxiv. 6;
• noun In these the metaphor precedes; in the following the simile is in the middle of the metaphor: “These metaphysic rights, entering into common life, like rays of light which pierce into a dense medium, are, by the laws of Nature, refracted from their straight line.” (Burke, Rev. in France.) In the same way the simile may come first. A comparison differs from a simile essentially in that the former fixes attention upon the subordinate object, while a simile fixes it upon the main one: thus, one verse of Shelley's “Ode to the Skylark“begins by saying that the skylark is like a poet, whose circumstances are thereupon detailed. Generally, on this account, the comparision is longer than the simile. The allegory personifies abstract things, usually at some length. A short allegory is Ps. Ixxx. 8–16. Spenser's “Faery Queene” is a series of allegories upon the virtues, and Bunyan's “Pilgrim's Progress” allegorizes Christian experiences. These are acknowledged to be the most perfect allegories in literature. The allegory is an extended simile, with the first object in the simile carefully left unmentioned. A parable is a story that is or might be true, and is used generally to teach some moral or religious truth: as. the three parables of God's great love for the sinner in luke xv. Socrates's story of the sailors who chose their steersman by lot, as suggesting the folly of a similar course in choosing the helmsman of the state, is a fine example of the parable of civil life. A fable differs from a parable in being improbable or impossible as fact, as in making trees choose a king, beasts talk, or frogs pray to Jupiter; it generally is short, and points a homely moral. See the definitions of apologue and trope.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Rhet.) A word or phrase by which anything is likened, in one or more of its aspects, to something else; a similitude; a poetical or imaginative comparison.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A figure of speech in which one thing is compared to another, in the case of English generally using like or as.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a figure of speech that expresses a resemblance between things of different kinds (usually formed with `like' or `as')