Means 'Wear A Condom' In A Nonchallant way, so your teachers/parents/boss/anyone else you dont want to kno ur gona have sex, wont notice what your REALLY talking about.
*In The Middle Of A Test.* guy1 "so mann, i was thinkin i was gone "hang out" wit Leah tonight.
Guy2 "hey, Be Cool, Bag Your Tool."
*Teacher looks confused and walks away.*
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!