Tathagata in Chinese / Japanese...

釋迦牟尼 is a transliteration of “Shakyamuni” or “Sakyamuni” in Chinese, Japanese, and old Korean.

The perceived meaning of the name is roughly translated as “Sage of the Sakyas.”
This same Buddha is also known as “Siddhartha Gautama,” “Gotama Buddha,” “Tathagata,” or simply, “The Supreme Buddha.”

Shakyamuni is the legendary man and prince who eventually established the Buddhist religion.

Note: Occasionally Romanized as “Siddhattha Gotama.”

This combination of characters is sometimes seen and used in South Korea and Japan as well (with the same meaning).

Note: 釋迦牟尼 came from the Sanskrit शाक्यमुनि and can also be romanized with diuretics as Śākyamuni.

悉達多 is the name Siddhartha (as in Siddhartha Gautama), the personal name for Śākyamuni.

This same Buddha is also known as “Shakyamuni Gautama,” “Gotama Buddha,” or “Tathagata.”

Siddhartha Gautama was a spiritual teacher in the northern region of the Indian subcontinent who founded Buddhism. He is generally seen by Buddhists as the Supreme Buddha (Sammāsambuddha) of known human history.

The actual meaning of this name in Chinese is the realization of all aims, or simply being prosperous.

This name is sometimes romanized from the original Sanskrit or Pali as Siddhattha (from Siddhattha Gotama), Siddharth, Siddhārtha, or Sarvāthasiddha.

Siddhārtha or Sarvāthasiddha can also be written as 悉達, 悉多, 悉多頞他, or 悉陀.

如來 is the name Tathāgata (Buddha's name for himself) in Chinese and Japanese.

This has many layers of meaning: Gone to the absolute, perfected one, he who comes as do all other Buddhas, he who took the absolute way of cause and effect, etc.