al·to·geth·er 
(ôl′tə-gĕthər)
(ôl′tə-gĕthər)adv.
1. Entirely; completely; utterly: lost the TV picture altogether; an altogether new approach.
2. With all included or counted; all told: There were altogether 20 people at the dinner.
3. On the whole; with everything considered: Altogether, I'm sorry it happened.
n.
A state of nudity. Often used with the: in the altogether.
[Middle English al togeder : al, all; see ALL + togeder, together; see TOGETHER.]
Usage Note: Altogether and all together do not mean the same thing. We use all together to indicate that the members of a group perform or undergo an action collectively: The nations stood all together. The prisoners were herded all together. All together is used only in sentences that can be rephrased so that all and together may be separated by other words: The books lay all together in a heap. All the books lay together in a heap.