Is cumming for a female the same as orgasm?

I'm not an expert on slang, but I'll take a stab at answering your question. One of the problems is the way that you spelled the word. To "come" is definitely a slang expression for having an orgasm and it applies to either sex. But the word "cum" is a slang expression for the male ejaculate, so I suppose technically, "cumming" would only apply to men. Now if you were speaking the word, since no one would know how you were spelling it, it could apply to either sex, but if you are going to write it and spell it the way you did, then I would say it is a male related word, though since it's all slang in any case, I'm not sure that there's much of a need to be perfectly correct when using such terms.