From Longman Dictionary of Contemporary Englishbrotherbroth‧er1 /ˈbrʌðə $ -ər/ ●●● S1 W1 noun [countable] 1 FAMILYa male who has the same parents as you → sister I have two brothers, William and Mark.elder/older/younger etc brother My younger brother is a doctor.little/kid brother (=younger brother) I have to take my little brother to school. My big brother (=older brother) has always looked after me. my twin brother2 spoken informal a word meaning a black man, used especially by other black men3 TALK TO somebodyMEMBERa male member of a group with the same interests, religion, profession etc as you4 RRC (plural brothers or brethren) a male member of a religious group, especially a monk Brother Justin5 American EnglishSEC a member of a fraternity (=a club of male university students)6 → brothers in arms → blood brother, half-brother, stepbrotherCOLLOCATIONSADJECTIVES/NOUN + brother an older/elder brotherI have two older brothers.a big brother (=older brother – used especially by or to children)Jake was my big brother and I admired him.a younger brotherDo you have any younger brothers?a little brother (also a kid brother American English) (=younger brother)My kid brother was always annoying me.a baby brother (=brother who is still a baby)Mum let me hold my new baby brother.a twin brotherLuke and his twin brother Sam went everywhere together.a half-brother (=brother with only one parent the same as yours)I never really liked my half-brother.a step-brother (=the son of your stepfather or stepmother)His dad’s new wife brought him two step-brothers.
Examples from the Corpus
brother• His decision to send her away from her home and brother into an alien world was interpreted as rejection.• He was friend, father, brother, neighbor, lover.• Personally, I don't believe the allegations which are being made against him and his brother.• My brother hangs out with people who beat people up as like a job.• It was not until March in 1782 that the brothers made the error that was the beginning of their undoing.• I have two brothers, James and Karl.• She remembers that people told them they looked alike, and they joked that they were brother and sister.• He came to the defense of his younger brother, Von, by swinging a chain at his attacker.big brother• Vincente caddied for him for a while but it was an awkward role for a big brother.• Let the older child get as involved as possible and point out how much the new baby loves her big brother.• Stewart was deeply moved to be back in the compelling presence of his big brother after five years.• First time my big brother comes to visit me in how many years has it been now?• When I told my big brother about the whole thing, he said I was bloody stupid.• My big brother Carl became the most utterly-spoiled and pampered child of all.• Michael's big brother is named Jonathan.• All my love, Your big brother Sam.brotherbrother2 interjection especially American English ANNOYused to show you are annoyed or surprised Oh, brother – I really don’t want to deal with this now.Origin brother1 Old English brothor