Abnormal and persistent fear of crossing streets, highways and other thoroughfares; fear of thoroughfares themselves. Sufferers experience anxiety even though they realize that streets, highways and other thoroughfares pose no threat commensurate with their fear. Formed from the Greek "gyrus" (turning or whirling) and the Greek "phobos" (fear). The first letter, "a," is privative--that is, it creates a negative. Thus, an agyrophobiac shuns or avoids the whirl of traffic.