look right/straight through (someone)

to behave as if you do not see someone when you look at them, either because you do not notice them or because you are ignoring them.

I'm sure I was at school with that girl, but she just looked straight through me.

• a banana republic
• a banana skin
• a Band-Aid
• a bang up job
• a baptism by fire
• a baptism of fire
• a bargaining chip
• a basket case
• a battle of nerves
• a battle of wills
• a battle of wits
• ABCs of
• ABCs of something
• a bean counter
• a bear hug
• a beast of burden
• a belly laugh
• a Bible-basher
• abide by
• abide by something
• a big ask
• a big cheese
• a big deal
• a big fish
• a big fish in a small pond