The name "Al-Ahsa" derives from an authentic Arabic geographic-hydrological term rather than from any particular story or event. "Al-Ahsa" is the plural of "hisa," a word that in Arabic denotes a sandy area underlain by a hard layer, such as rock or clay. When rain fell, water would seep down until it met this hard layer and pool above it. When people needed water, they would dig relatively shallow holes and find this stored freshwater. Because such "ahsa" formations were so abundant in this area, the name "Al-Ahsa" came to be used first as a geographic descriptor and later as the proper name of the entire region.
Hajar and Al-Ahsa: Two Names for One Region Across the Ages
Before the name "Al-Ahsa" became widespread, this area was known as "Hajar," the name under which the region appears in pre-Islamic and early Islamic sources. Some modern researchers suggest that this "Hajar" may be the same city known to the ancient Greeks as "Gerrha," though this identification remains a subject of scholarly debate.
Sources date the shift from the name "Hajar" to "Al-Ahsa" to the early 4th century AH (10th century CE), when Abu Tahir al-Jannabi, ruler of the Qarmatian state, built a new city near the site of Hajar and named it "Al-Ahsa" to serve as the seat of his rule.
"Al-Hofuf," meanwhile, is the name of the principal city that grew and expanded within the Al-Ahsa Oasis to become its capital. The name "Al-Hofuf" is thought to derive from the verb "haffa," which denotes the blowing of a light breeze.