Last week, I was buying a birthday gift for my roommate when I saw my grammar teacher Nancy at Del Amo Mall. I waved to Nancy to say hello. She just looked right at me and walked away! I was so shocked by her rude behavior!
On Monday, I asked her why she blew me off at the mall. I was relieved when she told me that she was going to pick up her new glasses and couldn't see anything until she got them. She just didn't recognize me! I'm happy to know that she didn't blow me off on purpose.
Jake: Hey, Tim! Are you going to Mark's party on Thursday?
Tim: I really want to, but we have tests on Friday morning. I need to study!
Jake: Oh! Don't worry about the tests! You'll be fine.
Tim: Besides, I have plans to study with Sheila.
Jake: You guys should blow off the study session and come to the party!
The idiom to blow off means to ignore something or someone in an obvious way.
In the first example, the student is shocked because her grammar teacher blew her off at the mall- she saw her and ignored her very obviously. Actually, her teacher did not blow her off / ignore her, she just couldn't see anything without her new glasses.
In the second example, Jake wants Tim to blow off his study session to attend a party. If he blows off studying, then he is ignoring his plan to study to go to the party.
This idiom comes from the LSI textbook "Spekaing Savvy." This book is used by LSI teachers in our Level 5 Speaking classes. For more information, please visit www.languagesystems.com