what the?

I got this recently...It was last night actually as I was struggling my head on my thermo book...I have found this sentence that sounds like this..."You should keep in mind that a formula that is not dimensionally homogeneous is definitely wrong, but a dimensionally homogeneous formula is not necessarily right"...hehe...as I read that and try to find out the meaning in a lying down position..I try to close my eyes just for a minute..and you know what?????the second thing I notice is, its already 7.51 a.m...huhu...I'm late to class already just for the sake of finding those meanings....