copepod, copepod crustacean - minute marine or freshwater crustaceans usually having six pairs of limbs on the thorax; some abundant in plankton and others parasitic on fish mussel shrimp, ostracod, seed shrimp - tiny marine and freshwater crustaceans with a shrimp-like body enclosed in a bivalve shell
time and a half(noun) a rate of pay that is 1.5 times the regular rate; for overtime work.
Confidence votes 109. Half life is the time taken for approximately half of the available nuclei in a sample of radioactive material to decay into something else. It's a characteristic of the isotope, for example, the half life of the isotope of iodine, I131 is 8.08 days. Half lives can vary from fractions of a second to thousands of years.