click

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

• noun A brief, sharp sound.
• noun A mechanical device, such as a pawl, that snaps into position.
• noun Computers An instance of pressing down and releasing a button on a pointing device, such as a mouse.
• noun Linguistics Any of various implosive stops, such as that of English tsk, produced by raising the back of the tongue to make contact with the palate and simultaneously closing the lips or touching the teeth or alveolar ridge with the tip and sides of the tongue, and found as phonemic consonants especially in the Khoisan and some Bantu languages.
• intransitive verb To produce a click or series of clicks.
• intransitive verb Computers To press down and release a button on a pointing device in order to select an item on a display screen or activate a command or function. Often used with on:
• intransitive verb To have good social or working relations; hit it off.
• intransitive verb To become clear; fall into place.
• intransitive verb To be a great success.
• intransitive verb To cause to click, as by striking together.
• intransitive verb To press down and release (a button on a pointing device).
• intransitive verb To press down and release a button on (a pointing device).
• intransitive verb To select or activate (an onscreen item) by pressing down and releasing a button on a pointing device.

from The Century Dictionary.

• To make a small sharp sound, or a succession of weak sharp sounds, as by a gentle blow; tick.
• To move with a clicking sound.
• Sometimes spelled klick.
• To snatch; clutch: as, he clicked it out o' my hands.
• noun A small sharp sound: as, the click of a latch; the click of a pistol.
• noun A cluck-like sound, used in the alphabets of certain languages, especially the Hottentot and neighboring tongues in South Africa.
• noun In machinery, a small bar which moves backward and forward, and at every forward stroke enters the teeth of a ratchet-wheel or rack, which it pushes forward, leaving it at rest during the backward stroke. Also called clicker.
• noun The latch of a door.
• To overreach, as a horse, and strike the front of the hind foot against the shoe of the fore foot, making a clicking sound.

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

• intransitive verb To make a slight, sharp noise (or a succession of such noises), as by gentle striking; to tick.
• transitive verb To move with the sound of a click.
• transitive verb To cause to make a clicking noise, as by striking together, or against something.
• noun A slight sharp noise, such as is made by the cocking of a pistol.
• noun A kind of articulation used by the natives of Southern Africa, consisting in a sudden withdrawal of the end or some other portion of the tongue from a part of the mouth with which it is in contact, whereby a sharp, clicking sound is produced. The sounds are four in number, and are called cerebral, palatal, dental, and lateral clicks or clucks, the latter being the noise ordinarily used in urging a horse forward.
• transitive verb Prov. Eng. To snatch.
• noun A detent, pawl, or ratchet, as that which catches the cogs of a ratchet wheel to prevent backward motion. See Illust. of ratched wheel.
• noun Prov. Eng. The latch of a door.

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

• noun A detent, pawl, or ratchet, such as that which catches the cogs of a ratchet wheel to prevent backward motion.
• noun UK, dialect The latch of a door.
• noun Alternative spelling of klick.
• noun A brief, sharp, not particularly loud, relatively high-pitched sound produced by the impact something small and hard against something hard, such as by the operation of a switch, a lock or a latch, or a finger pressed against the thumb and then released to strike the hand.
• noun phonetics An ingressive sound made by coarticulating a velar or uvular closure with another closure.
• noun Sound made by a dolphin.
• noun The act of operating a switch, etc., so that it clicks.
• noun The act of pressing a button on a computer mouse.
• noun this sense?) The term used to show approval, acceptance, or general agreement.
• verb transitive To cause to make a click, eg to operate (a switch, etc) so that it makes a click.
• verb transitive (direct and indirect) To press and release (a button on a computer mouse).
• verb transitive To select a software item using, usually, but not always, the pressing of a mouse button.
• verb transitive, advertising To visit a web site.
• verb intransitive To emit a click.
• verb intransitive To click the left button of a computer mouse while pointing.
• verb intransitive To make sense suddenly.
• verb intransitive To get on well.
• interjection The sound of a click.