The Collaborative International Dictionary of English v.0.48:

clocks \clocks\ n.
   1. European weed naturalized in the southwestern U. S. and
      Mexico (Erodium cicutarium), having reddish decumbent
      stems with small fernlike leaves and small deep
      reddish-lavender flowers followed by slender pinlike
      fruits that stick straight up; it is often grown for
      forage.

   Syn: redstem storksbill, alfilaria, alfileria, filaree,
        filaria, pin grass, pin clover, Erodium cicutarium.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

clocks
    n 1: European weed naturalized in southwestern United States and
         Mexico having reddish decumbent stems with small fernlike
         leaves and small deep reddish-lavender flowers followed by
         slender fruits that stick straight up; often grown for
         forage [syn: redstem storksbill, alfilaria,
         alfileria, filaree, filaria, clocks, pin grass,
         pin clover, Erodium cicutarium]

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

clocks
 n.

    Processor logic cycles, so called because each generally corresponds to one
    clock pulse in the processor's timing. The relative execution times of
    instructions on a machine are usually discussed in clocks rather than
    absolute fractions of a second; one good reason for this is that clock
    speeds for various models of the machine may increase as technology
    improves, and it is usually the relative times one is interested in when
    discussing the instruction set. Compare cycle, jiffy.