| biological | (adj) pertaining to biology or to life and living things, Syn. biologic |
| biological | (adj) of parents and children; related by blood, Ant. adoptive, Example: biological child |
| biological agent | (n) any bacterium or virus or toxin that could be used in biological warfare, Syn. biohazard |
| biological clock | (n) an innate mechanism in living organisms that controls the periodicity of many physiological functions |
| biological defense | (n) procedures involved in taking defensive measures against attacks using biological agents, Syn. biological defence, biodefence, biodefense |
| biological group | (n) a group of plants or animals |
| biologically | (adv) with respect to biology, Example: biologically related |
| biological research | (n) scientific research conducted by biologists |
| biological time | (n) the time of various biological processes |
| biological warfare | (n) the use of bacteria or viruses or toxins to destroy men and animals or food, Syn. biologic attack, BW, bioattack, biological attack |