'伞形' (sǎn xíng) is a compound adjective meaning 'umbrella-shaped' — literally combining 伞 (sǎn), 'umbrella', and 形 (xíng), 'shape' or 'form'. It describes any object, structure, or natural feature whose outline or arrangement resembles an open umbrella: typically broad and rounded at the top with a narrower base or central stalk. The term is widely used in scientific and descriptive contexts, especially in biology and botany.

This word frequently appears when classifying fungi (e.g., certain mushrooms with broad caps), plants (like the flower clusters of fennel or parsley, which radiate from a central point), and even animal formations (e.g., coral polyps or jellyfish bells). Though visually precise, it is neutral in register — neither formal nor colloquial — and functions attributively before nouns (e.g., 伞形花序, 'umbellate inflorescence') or predicatively with 是 or 很 (e.g., 这个蘑菇的菌盖是伞形的).