Indicates that something is also the case — that in addition to what was just mentioned, the thing also has another quality or role. Formal/literary tone.
彼は医者であると同時に、小説家でもある。
He is a doctor and also a novelist.
この建物は美術館であるとともに、文化センターでもある。
This building is a museum and also a cultural center.
彼女の言葉は励ましであると同時に、厳しい忠告でもある。
Her words are encouragement, and at the same time somewhat stern advice.
Used to suggest or imply that something is or could be something (often somewhat tentative or rhetorical) — like saying 'it is, or it might be, ...' or 'it could be considered ...'.
あの説明は説明でもあるし、言い訳でもあるように聞こえる。
That explanation sounds like an explanation, but also like an excuse.
彼の笑顔は親切でもあるが、どこか作りものでもある気がする。
His smile is kind, but somehow it also feels a bit put-on.