Definition of Half-life

1. Noun. The time required for something to fall to half its initial value (in particular, the time for half the atoms in a radioactive substance to disintegrate).

Exact synonyms: Half Life
Generic synonyms: Period, Period Of Time, Time Period

Medical Definition of Half-life

1. 1. The period over which the concentration of a specified chemical or drug takes to fall to half its original concentration in the specified fluid or blood. 2. The time required to reduce the amount of a radionuclide to one-half the amount originally present. Physical or radioactive half-life refers to reduction of activity by radioactive decay, biological half-life refers to biological elimination from the body and effective half-life refers to the combined action of radioactive decay and biological elimination. (16 Dec 1997)

Lexicographical Neighbors of Half-life

half-deck
half-fish
half-free morel
half-glass spectacles
half-hapten
half-hardy
half-hearted
half-heartedly
half-holiday
half-hour
half-hourly
half-inferior
half-intensity
half-length
half-life (current term)
half-life (current term)
half-light
half-mast
half-moon
half-moon
half-pay
half-pint
half-price
half-ray
half-reactions
half-relief
half-seas-over
half-size
half-slip
half-term

Other Resources:

Search for Half-life on Dictionary.com!Search for Half-life on Thesaurus.com!Search for Half-life on Google!Search for Half-life on Wikipedia!