The shell bone script of character Outside is
The left is 卜 （Divine, see Post 280), the right one is compound character with 卜 on the left and 内 (Inside, see Post 249). Both has 卜. The simple explanation is that the divination is hold outside, not inside. The second character includes 内 (Inside) to emphasize, 卜 is divination outside.
The bronze script of the character is
Let me explain the meaning of the bronze script.
The left is 夕（Evening, see Post 52 and 53), the right is 卜. 夕 is moon in the evening. There is dispute on this one. Some people believe that the divination is held outside in the evening. Others believe that the divination was normally held in the day time, so if it was held in the evening, would be a out of predication or normal expectation.
I prefer the first: the divination is held outside in the evening. I am not sure if divination was held in day time or evenings, but I think that divination in evenings should not be unusual because in the day time, people went for hunting or some other work, came home in the evening. It should be normal to hold divination in the evenings.
The big seal script of the character Outside is
The small seal script of character Outside is
The clerical script of character Outside is
Its Pinyin is Wai4.