idée fixe/ˌeeday ʹfeeks (French ide fiks)/ /ˌeeday ʹfeeks/ noun (pl idées fixes /ˌeeday ʹfeeks/)

• bipinnate
• biplane
• bipolar
• bipolar disorder
• BIR
• birch
• bird
• birdbath
• birdbrain
• birdcage
• birdcall
• bird dog
• birder
• bird flu
• bird-foot
• birdie
• birdlime
• bird-nesting
• bird of paradise
• bird of passage
• bird of prey
• birdseed
• bird's-eye
• bird's-eye view
• bird's-foot