Among Arab groups, a term denoting a tribe, clan, family, or other patrilineal filiation.
It often refers to a ruling line or dynasty and generally precedes a substantive name (e.g., Āl Saʽūd) but is not connected by a hyphen; it is unrelated to the Arabic definite article, al- . In Britannica Concise Encyclopedia , entries for Arab tribal and dynastic groups are alphabetized under the substantive (e.g., for Āl Saʽūd, see Saūd dynasty ).