ear

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

• noun The seed-bearing spike of a cereal plant, such as corn.
• intransitive verb To form or grow ears.
• noun The vertebrate organ of hearing, responsible for maintaining equilibrium as well as sensing sound and divided in mammals into the external ear, the middle ear, and the inner ear.
• noun The part of this organ that is externally visible.
• noun An invertebrate organ analogous to the mammalian ear.
• noun The sense of hearing.
• noun Sensitivity or receptiveness to sound, especially.
• noun Sharpness or refinement of hearing.
• noun The ability to play a passage of music solely from hearing it.
• noun Responsiveness to the sounds or forms of spoken language.
• noun Sympathetic or favorable attention.
• noun Something resembling the external ear in position or shape, especially.
• noun A flexible tuft of feathers located above the eyes of certain birds, such as owls, that functions in visual communication but not in hearing.
• noun A projecting handle, as on a vase or pitcher.
• noun A small box in the upper corner of the page in a newspaper or periodical that contains a printed notice, such as promotional material or weather information.
• noun Informal Headphones.
• idiom (all ears) Acutely attentive.
• idiom (coming out of (one's) ears) In more than adequate amounts; overabundant.
• idiom (give/lend) To pay close attention; listen attentively.
• idiom (have/keep) To be on the watch for new trends or information.
• idiom (in one ear and out the other) Without any influence or effect; unheeded.
• idiom (its/someone's) In a state of amazement, excitement, or uproar.
• idiom (up to (one's) ears) Deeply involved or occupied fully.

from The Century Dictionary.

• To shoot, as an ear; form ears, as corn.
• To cultivate with a plow; plow; till.
• Early.
• noun A kidney.
• noun A spike or head of corn or grain; that part of a cereal plant which contains the flowers and seed.
• To listen to; hear with attention.
• noun The organ of hearing; the apparatus of audition; the acoustic sense-organ; any mechanism by which an animal receives the impact of sound-waves and perceives them as sound.
• noun The external ear alone, known as the pinna, auricle, or concha: as, the horse laid his ears back.
• noun In ornithology: The auriculars or packet of auricular feathers which cover the external ear-passage of a bird.
• noun A plumicorn or corniplume; one of the “horns” of an owl.
• noun The sense of hearing; the power of distinguishing sounds; the power of nice perception of the differences of sound.
• noun Specifically, in music, the capacity to appreciate, analyze, and reproduce musical compositions by hearing them; sensitiveness to musical intonation and to differences of pitch and quality in musical sounds: as, a correct ear. Sometimes called a musical ear.
• noun A careful or favorable hearing; attention; heed.
• noun Disposition to listen; judgment; taste.
• noun A part of any inanimate object having some likeness to the external ear.
• noun In architecture, same as crosset, 1 .
• noun An aural instrument for the use of very deaf persons. It has a large pavilion secured by a swivel to a stand upon the floor, and an elastic tube with a nozle to be held to the ear.

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

• intransitive verb To put forth ears in growing; to form ears, as grain.
• noun The spike or head of any cereal (as, wheat, rye, barley, Indian corn, etc.), containing the kernels.
• transitive verb To plow or till; to cultivate.
• transitive verb Sportive To take in with the ears; to hear.
• noun The organ of hearing; the external ear.
• noun The sense of hearing; the perception of sounds; the power of discriminating between different tones; ; -- in the singular only.
• noun That which resembles in shape or position the ear of an animal; any prominence or projection on an object, -- usually one for support or attachment; a lug; a handle. The ears of a boat are outside kneepieces near the bow. See Illust. of Bell.