The term "un-condensed" suggests that something has not been reduced in size or volume. The antonyms for this word can describe how something has been compressed, compacted, or reduced. The word "condensed" can mean to make something more concise, so the antonyms could include terms such as expanded, elongated, or broadened. Other opposing terms for "un-condensed" could include thickened, deepened, densified, or intensified. These antonyms all suggest that something has become more concentrated or focused, which is the opposite of "un-condensed." So, depending on the context, there are several words that can be used as antonyms for "un-condensed.