無窮 is the Chinese and Korean word meaning infinity, eternity, infinitude, infinite or endless.

無窮 literally translates as “without [ever becoming] exhausted/poor,” and in that context, can mean “inexhaustible” or “boundless” but this is usually read as “without end.” Some extended definitions include eternity, infinitude, or immortality.

In certain contexts, it can mean “immortality.”

The first character means “never” or “not.” The second means “exhausted,” “finished,” or “ending.”

Note: 無窮 is a Japanese word but rarely used in modern Japan.

無限 is the Chinese and Japanese word meaning infinity, unlimited or unbounded.

無限 literally translates as “without limits” or “without [being] bound.”

The first character means “never” or “not,” like the prefix “un-.”

The second means “limited,” “restricted,” or “bound.”

Please note that the Japanese definition leans more toward “infinity” and the Chinese is more about being “boundless” or “without limits.”

In Korean, this means infinity, infinitude, or boundlessness. But in Korean, this term has many interpretations or contexts, so your intended meaning might be vague or ambiguous.

四無量心 is the cattāri brahmavihārā or catvāri apramāṇāni.

The four immeasurables, or infinite Buddha-states of mind. These four dhyānas include:
1. 慈無量心 boundless kindness, maitrī, or bestowing of joy or happiness.
2. 悲無量心 boundless pity, karuṇā, to save from suffering.
3. 喜無量心 boundless joy, muditā, on seeing others rescued from suffering.
4. 捨無量心 limitless indifference, upekṣā, i.e., rising above these emotions or giving up all things.

漫瀾 is the Chinese, Japanese Kanji, and old Korean Hanja for “Having no boundaries or limitations.”

This literally talks of the vastness of an ocean or river.

Character breakdown:
漫 = free; unrestrained; to inundate; overflowing; boundless.
澜 = swelling water; large wave.