tick¹ / tik/ • n. 1. a regular short, sharp sound, esp. that made every second by a clock or watch. ∎ Brit. inf. a moment (used esp. to reassure someone that one will return or be ready very soon): I'll be with you in a tick.2. chiefly Brit. a check mark.3. Stock Market the smallest recognized amount by which a price of a security or future may fluctuate.• v. 1. [intr.] (of a clock or other mechanical device) make regular short sharp sounds, typically for every second of time passing: I could hear the clock ticking. ∎  (tick away/by/past) (of time) pass (used esp. when someone is pressed for time or keenly awaiting an event): the minutes were ticking away till the actor's appearance. ∎  [tr.] (tick something away) (of a clock or watch) mark the passing of time with regular short sharp sounds: the little clock ticked the precious minutes away. ∎  proceed or progress: her book was ticking along nicely.2. chiefly Brit. [tr.] mark (an item) with a check mark, typically to show that it has been chosen, checked, or approved: just tick the appropriate box below. ∎  (tick something off) list items one by one in one's mind or during a speech: he ticked the points off on his fingers.PHRASES: what makes someone tick inf. what motivates someone: people are curious to know what makes these men tick.PHRASAL VERBS: tick someone offinf. make someone annoyed or angry.tick over (of an engine) idle. ∎  work or function at a basic or minimum level: they are keeping things ticking over until their father returns.tick² • n. a parasitic arachnid (suborder Ixodida, order Acarina) that attaches itself to the skin of a terrestrial vertebrate from which it sucks blood, leaving the host when sated. Some species transmit diseases, including tularemia and Lyme disease. ∎ inf. a parasitic louse fly.tick³ • n. a fabric case stuffed with feathers or other material to form a mattress or pillow. ∎ short for ticking.tick⁴ • n. (in phrase on tick) chiefly Brit. or dated on credit.

tick (tik) n. a bloodsucking parasite belonging to the order of arthropods (Acarina) that also includes the mites. Tick bites can cause serious skin lesions and occasionally paralysis, and certain tick species transmit typhus, Lyme disease, and relapsing fever. Dimethyl phthalate is used as a tick repellent. t. fever any infectious disease transmitted by ticks, especially Rocky Mountain spotted fever.

tick3 case or cover of a mattress or pillow, (hence) material of this. XV (tikke, tēke, tȳke). corr. to and prob. immed. — MLG., MDu. tīke and MDu. tīke (Du. tijk), rel. to OHG. ziahha, ziecha (G. zieche bed-tick, pillow-case); WGmc.- L. thēca — Gr. thḗkē case, f. IE. *dhē- place (see DO1).

tick2 (dial.) touch or tap lightly, esp. toy, dally XIII; make short quick beats XVIII; mark with a dash, etc. XIX. prob. imit.
So sb. slight touch XV; quick dry sound XVII; small dot or dash XIX. The parallel LG. tikk touch, instant, Du. tik pat, touch, tikken pat, tick, OHG. zekōn pluck, etc., may point to a WGmc. base, or the various forms may be independent expressive formations.

tick Any of numerous species of wingless, bloodsucking arachnids, the most notable of which are ectoparasites of vertebrates and invertebrates. Many species carry diseases (some fatal) in wild and domesticated animals, and in humans. Length: to 3mm (0.1in). Class Arachnida; order Acarina.