1. Clothing: This is the most common meaning. It refers to clothes, especially outer garments like robes or dresses.
2. Quantity: It can also mean "fourth" or "quarter", as in "rub` al-thuman" (ربع الثمان) which means "one-quarter of eight".
3. Name: "Ruba" can also be a female name in Arabic.
4. Poetry: In traditional Arabic poetry, "ruba'i" (رباعی) is a four-line stanza often used for lyrical or philosophical themes.
To understand the exact meaning of "ruba" in a specific context, you need to consider the surrounding words and the overall meaning of the sentence.