3 ADJ [usu ADJ n] Biological weapons and biological warfare involve the use of bacteria or other living organisms in order to attack human beings, animals, or plants. □ Such a war could result in the use of chemical and biological weapons.
4 ADJ [ADJ n] Biological pest control is the use of bacteria or other living organisms in order to destroy other organisms which are harmful to plants or crops. □ …Jim Litsinger, a consultant on biological control of agricultural pests.
5 ADJ [ADJ n] A child's biological parents are the man and woman who caused him or her to be born, rather than other adults who look after him or her. □ …foster parents for young teenagers whose biological parents have rejected them.
bio|lo gi|cal clo ck (biological clocks ) N‑COUNT [oft poss N ] Your biological clock is your body's way of registering time. It does not rely on events such as day or night, but on factors such as your habits, your age, and chemical changes taking place in your body. □ For women, the 'biological clock' governs the time for having children.
bio|lo gi|cal di|ve r|sity N‑UNCOUNT Biological diversity is the same as biodiversity .
bi|ol|ogy /ba I ɒ lədʒi/
1 N‑UNCOUNT Biology is the science which is concerned with the study of living things. ● bi|olo|gist /ba I ɒ lədʒ I st/ (biologists ) N‑COUNT □ …biologists studying the fruit fly.
2 N‑UNCOUNT The biology of a living thing is the way in which its body or cells behave. □ The biology of these diseases is terribly complicated. □ …human biology.
3 → see also molecular biology
bio|medi|cal /ba I oʊme d I k ə l/ ADJ [ADJ n] Biomedical research examines the effects of drugs and medical techniques on the biological systems of living creatures. □ Biomedical research will enable many individuals infected with the disease to live longer, more comfortable lives.
bio|met|ric /ba I oʊme tr I k/ ADJ [ADJ n] Biometric tests and devices use biological information about a person to create a detailed record of their personal characteristics. □ …the use of biometric information such as fingerprints.
bi|on|ic /ba I ɒ n I k/ ADJ [usu ADJ n] In science fiction books or films, a bionic person is someone who has special powers, such as being exceptionally strong or having exceptionally good sight, because parts of their body have been replaced by electronic machinery. □ …the Bionic Woman.
bio|pic /ba I oʊp I k/ (biopics ) N‑COUNT A biopic is a film that tells the story of someone's life.
bi|op|sy /ba I ɒpsi/ (biopsies ) N‑VAR A biopsy is the removal and examination of fluids or tissue from a patient's body in order to discover why they are ill.
bio|sphere /ba I oʊsf I ə r / N‑SING The biosphere is the part of the earth's surface and atmosphere where there are living things. [TECHNICAL ]
bio|tech /ba I oʊtek/ N‑UNCOUNT [usu N n] Biotech means the same as biotechnology . □ …the biotech industry.
bio|tech|no|logi|cal /ba I oʊte knəlɒ dʒ I k ə l/ ADJ [ADJ n] Biotechnological means relating to biotechnology. [TECHNICAL ] □ …modern biotechnological methods of genetic manipulation.
bio|tech|nol|ogy /ba I oʊteknɒ lədʒi/ N‑UNCOUNT Biotechnology is the use of living parts such as cells or bacteria in industry and technology. [TECHNICAL ] ● bio|tech|nolo|gist /ba I oʊteknɒ lədʒ I st/ (biotechnologists ) N‑COUNT □ …biotechnologists turning proteins into pharmaceuticals.
bio|ter|ror|ism /ba I oʊte rər I zəm/ also bio-terrorism N‑UNCOUNT Bioterrorism is terrorism that involves the use of biological weapons. □ …the threat of bioterrorism. ● bio|ter|ror|ist /ba I oʊte rər I st/ (bioterrorists ) N‑COUNT [oft N n] □ …the war against bioterrorists. □ …a bioterrorist attack.
bio|weap|on /ba I oʊwe pən/ also bio-weapon (bioweapons ) N‑COUNT Bioweapons are biological weapons, which involve the use of bacteria or other living organisms in order to destroy other organisms which are harmful to plants and crops.
bi|par|ti|san /ba I pɑː r t I zæ n, [AM ] ba I pɑː rt I z ə n/ ADJ [usu ADJ n] Bipartisan means concerning or involving two different political parties or groups. □ …a bipartisan approach to educational reform.
bi|ped /ba I ped/ (bipeds ) N‑COUNT A biped is a creature with two legs. [TECHNICAL ]
bi|plane /ba I ple I n/ (biplanes ) N‑COUNT A biplane is an old-fashioned type of aeroplane with two pairs of wings, one above the other.
bi|po|lar /ba I poʊ lə r / ADJ [usu ADJ n] Bipolar systems or situations are dominated by two strong and opposing opinions or elements. [FORMAL ] □ …the bipolar world of the Cold War years.
bi|po |lar dis|o r|der (bipolar disorders ) N‑VAR Bipolar disorder is a mental illness in which a person's state of mind changes between extreme happiness and extreme depression.
birch /bɜː r tʃ/ (birches ) N‑VAR A birch or a birch tree is a type of tall tree with thin branches.
bird ◆◆◇ /bɜː r d/ (birds )
1 N‑COUNT A bird is a creature with feathers and wings. Female birds lay eggs. Most birds can fly.
2 N‑COUNT Some men refer to young women as birds . This use could cause offence. [BRIT , INFORMAL ]
3 → see also early bird , game bird
4 PHRASE If you refer to two people as birds of a feather , you mean that they have the same interests or are very similar.
5 PHRASE A bird in the hand is something that you already have and do not want to risk losing by trying to get something else.
6 PHRASE If you say that a little bird told you about something, you mean that someone has told you about it, but you do not want to say who it was.