"so so" = neither good nor bad neither this nor the other average It's a phrase you hear in Asia actually. We don't really use it over here. The phrase was invented in the Asian speaking world in order to translate a word there that doesn't really exist in English. ^_^

'so-so' can be used as an adjective or an adverb. adjective = neither very good nor very bad, passable. 'A so-so performance.' 'feeling so-so' adverb = neither very well nor very poorly, passably. ' I swam so-so, but better than yesterday'