One born in the late 1940s or '50s

• 1950's-60's adolescent
• Fortysomething, say
• Someone born in the decade after WWII
• Person born in the 1950s
• Postwar child
• Person born between 1946 and 1965
• One born during a period of sharp increase in the birthrate
• Gen Xer's parent, perhaps

Wiktionary Word definitions in Wiktionary
n. (alternative spelling of baby boomer English)