- Blood typing
- Blood vessel
- Blood viscosity
- Blood volume
- Blood-brain barrier
- Blood-testis barrier
- Bloodstream infections
- Bloom
- Bloom filters
- Bloom syndrome
- Blossom algorithm
- Blot
- Blotting
- Blow molding
- Blower door
- Blowfish
- Blowing agents
- Blowing snow
- Blowout preventer
- Blowouts
- Blowtorch
- Blue Angel
- Blue Gene
- Blue and white porcelain
- Blue baby syndrome
- Blue carbon
- Blue economy
- Blue ice
- Blue laser
- Blue light
- Blue shift
- Blue whales
- BlueBorne
- BlueZ
- Blueprint
- Blueschist
- Bluestone
- Bluetooth
- Bluetooth stack
- Bluff
- Bluing
- Blunt trauma
- Blurred vision
- Board feet
- Boarding
- Boardwalk
- Boat
- Boat building
- Bochner integral
- Bode plot
- Bodipy
- Body area network
- Body composition
- Body fat percentage
- Body forces
- Body hair
- Body image
- Body in white
- Body proportions
- Body roll
- Body style
- Boehmite
- Bog iron
- Bogies
- Bogoliubov quasiparticle
- Bogoliubov transformation
- Bohr effect
- Bohr magneton
- Bohr radius
- Boiler blowdown
- Boiler feedwater
- Boiler feedwater pump
- Boiler room
- Boiler water
- Boilers
- Boiling
- Boiling chips
- Boiling point
- Boiling-point elevation
- Bold
- Bollard pull
- Bollards
- Bollinger Bands
- Bologna Process
- Bolt
- Bolt circle
- Bolted joint
- Boltzmann constant
- Boltzmann distribution
- Boltzmann equation
- Boltzmann machines
- Bolus
- Bombardier
- Bombardier Transportation
- Bombesin
- Bombesin-like peptides
- Bombs
- Bombykol
- Bond cleavage
- Bond dissociation energy
- Bond energy
- Bond graphs
- Bond length
- Bond order
- Bond-dissociation energy
- Bonding molecular orbital
- Bonding orbitals
- Bone
- Bone age
- Bone ash
- Bone cement
- Bone char
- Bone china
- Bone conduction
- Bone density
- Bone fractures
- Bone graft
- Bone grafting
- Bone growth factor
- Bone healing
- Bone marrow
- Bone marrow suppression
- Bone marrow transplant
- Bone marrow-derived macrophages
- Bone meal
- Bone morphogenetic protein 2
- Bone morphogenetic protein 4
- Bone morphogenetic protein 7
- Bone pain
- Bone remodeling
- Bone resorption
- Bone sarcoma
- Bone scan
- Bone scintigraphy
- Bone sialoprotein
- Bone spurs
- Bone wax
- Bonferroni correction
- Boninite
- Bonner spheres
- Bonnet
- Bony labyrinth
- Boojum
- Book value
- Bookmarking
- Bookmarklets
- Boolean
- Boolean algebra
- Boolean expression
- Boolean function