The Collaborative International Dictionary of English v.0.48:
Semiofficial \Sem`i*of*fi"cial\, a. Half official; having some official authority or importance; as, a semiofficial statement. -- Sem`i*of*fi"cial*ly, adv. [1913 Webster] Semiology SemiographyWordNet (r) 3.0 (2006):
semiofficial adj 1: having some official authority or sanction