[1920–25; blasto- + -spore]This word is first recorded in the period 1920–25. Other words that entered Englishat around the same time include: Unknown Soldier, follow-up, self-service, ski jump, superpowerblasto- is a combining form meaning “bud, sprout,” “embryo,” “formative cells or cell layer,”used in the formation of compound words. Other words that use the affix blasto- include: blastoderm, blastomere, blastopore, blastosphere, blastostyle