The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, n. [LL. techa, teca, L. theca case, Gr. ?, fr. ? to
   put. See Thesis.]
   1. The cover, or case, of a bed, mattress, etc., which
      contains the straw, feathers, hair, or other filling.
      [1913 Webster]

   2. Ticking. See Ticking, n.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, v. i. [imp. & p. p. Ticked; p. pr. & vb. n.
   Ticking.] [Probably of imitative origin; cf. D. tikken, LG.
   ticken.]
   1. To make a small or repeating noise by beating or
      otherwise, as a watch does; to beat.
      [1913 Webster]

   2. To strike gently; to pat.
      [1913 Webster]

            Stand not ticking and toying at the branches.
                                                  --Latimer.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, n. [Abbrev. from ticket.]
   Credit; trust; as, to buy on, or upon, tick.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, v. i.
   1. To go on trust, or credit.
      [1913 Webster]

   2. To give tick; to trust.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, n. [OE. tike, teke; akin to D. teek, G. zecke. Cf.
   Tike a tick.] (Zool.)
      (a) Any one of numerous species of large parasitic mites
          which attach themselves to, and suck the blood of,
          cattle, dogs, and many other animals. When filled with
          blood they become ovate, much swollen, and usually
          livid red in color. Some of the species often attach
          themselves to the human body. The young are active and
          have at first but six legs.
      (b) Any one of several species of dipterous insects having
          a flattened and usually wingless body, as the bird
          ticks (see under Bird) and sheep tick (see under
          Sheep).
          [1913 Webster]

   Tick bean, a small bean used for feeding horses and other
      animals.

   Tick trefoil (Bot.), a name given to many plants of the
      leguminous genus Desmodium, which have trifoliate
      leaves, and joined pods roughened with minute hooked hairs
      by which the joints adhere to clothing and to the fleece
      of sheep.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, n.
   1. A quick, audible beat, as of a clock.
      [1913 Webster]

   2. Any small mark intended to direct attention to something,
      or to serve as a check. --Dickens.
      [1913 Webster]

   3. (Zool.) The whinchat; -- so called from its note. [Prov.
      Eng.]
      [1913 Webster]

   Death tick. (Zool.) See Deathwatch.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tick \Tick\, v. t.
   To check off by means of a tick or any small mark; to score.
   [1913 Webster]

         When I had got all my responsibilities down upon my
         list, I compared each with the bill and ticked it off.
                                                  --Dickens.
   [1913 Webster]

WordNet (r) 3.0 (2006):

tick
    n 1: a metallic tapping sound; "he counted the ticks of the
         clock" [syn: tick, ticking]
    2: any of two families of small parasitic arachnids with barbed
       proboscis; feed on blood of warm-blooded animals
    3: a mark indicating that something has been noted or completed
       etc.; "as he called the role he put a check mark by each
       student's name" [syn: check mark, check, tick]
    4: a light mattress
    v 1: make a clicking or ticking sound; "The clock ticked away"
         [syn: click, tick]
    2: make a sound like a clock or a timer; "the clocks were
       ticking"; "the grandfather clock beat midnight" [syn: tick,
       ticktock, ticktack, beat]
    3: sew; "tick a mattress" [syn: tick, retick]
    4: put a check mark on or near or next to; "Please check each
       name on the list"; "tick off the items"; "mark off the units"
       [syn: check, check off, mark, mark off, tick off,
       tick]

Moby Thesaurus II by Grady Ward, 1.0:

218 Moby Thesaurus words for "tick":
   act, arachnid, arthropod, bank credit, be effective, be in action,
   beat, bedbug, beetle, birthmark, blaze, blaze a trail, blemish,
   bloodsucker, blotch, book credit, borrowing power, brand, breath,
   bug, bump, cash credit, caste mark, caterpillar, centipede, chalk,
   chalk up, check, check off, checkmark, chilopod, chink, cicatrix,
   cicatrize, click, clicking, clink, clop, clump, clunk,
   commercial credit, consumer credit, coup, crack, credit,
   credit insurance, credit rating, credit union, crump, cut,
   daddy longlegs, dapple, dash, define, delimit, demarcate, diplopod,
   discolor, discoloration, dot, drum, dull thud, earmark, engrave,
   engraving, flash, fleck, flick, flump, fly, freckle, function,
   gash, go, go pitapat, graving, hack, half a jiffy, half a mo,
   half a second, half a shake, harvestman, hatch, have effect,
   have free play, have play, hexapod, hire purchase plan, impress,
   imprint, insect, installment credit, installment plan, instant,
   investment credit, jiff, jiffy, jot, larva, leech, lentigo, line,
   line of credit, macula, maggot, make a mark, mark, mark off,
   mark out, marking, microsecond, militate, millepede, millipede,
   millisecond, minute, mite, mole, moment, mosquito, mottle,
   never-never, nevus, nick, notch, nymph, operate, pad, palpitate,
   pant, parasite, pat, patch, patter, pencil, pepper, percolate,
   perform, perk, pitapat, pitter-patter, play, plump, plunk, point,
   polka dot, pop, prick, print, pulsate, pulse, punch, punctuate,
   puncture, rap, rating, riddle, run, scar, scarification, scarify,
   score, scorpion, scotch, scratch, scratching, seal, seam, sec,
   second, shake, speck, speckle, spider, splash, split second,
   splotch, spot, stain, stamp, stigma, stigmatize, strawberry mark,
   streak, striate, stripe, stroke, take effect, tap, tarantula,
   tattoo, tattoo mark, tax credit, throb, thud, thump, tick off,
   ticking, ticktack, ticktick, ticktock, tinkle, tittle, trace,
   trice, trust, tunk, twink, twinkle, twinkling, twitch, two shakes,
   underline, underscore, watermark, wink, wood tick, work



The Jargon File (version 4.4.7, 29 Dec 2003):

tick
 n.

    1. A jiffy (sense 1).

    2. In simulations, the discrete unit of time that passes between iterations
    of the simulation mechanism. In AI applications, this amount of time is
    often left unspecified, since the only constraint of interest is the
    ordering of events. This sort of AI simulation is often pejoratively
    referred to as tick-tick-tick simulation, especially when the issue of
    simultaneity of events with long, independent chains of causes is handwave
    d.

    3. In the FORTH language, a single quote character.


The Free On-line Dictionary of Computing (30 December 2018):

tick

   1. A jiffy (sense 1).  2. In simulations, the discrete unit
   of time that passes between iterations of the simulation
   mechanism.  In AI applications, this amount of time is often
   left unspecified, since the only constraint of interest is the
   ordering of events.  This sort of AI simulation is often
   pejoratively referred to as "tick-tick-tick" simulation,
   especially when the issue of simultaneity of events with long,
   independent chains of causes is handwaved.  3. In the FORTH
   language, a single quote character.

   [Jargon File]


Bouvier's Law Dictionary, Revised 6th Ed (1856):

TICK, contracts. Credit; as, if a servant usually buy for the master upon
tick, and the servant buy something without the master's order, yet, if the
master were trusted by the trader, he is liable. 1 Show. 95; 3 Keb. 625; 10
Mod. 111; 3 Esp. R. 214; 4 Esp. R. 174.