Meaning

noun loosely matted plant with moss-like foliage studded with tiny starry four-petaled white blossoms; mountains of central and southern Europe

noun low-growing herb having clusters of small white four-petaled flowers

noun low-growing chiefly perennial plant usually with small white flowers suitable for e.g. rock gardens

originFrom sand + wort.

Etymology from Wiktionary, CC BY-SA 3.0