a combining form meaning “bud, sprout,” “embryo,” “formative cells or cell layer,” used in the formation of compound words: blastosphere.
Also especially before a vowel, blast-.
See also -blast.
Origin of blasto-
< Greek, combining form of blastós a bud, sprout
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
(in biology) indicating an embryo or bud or the process of buddingblastoderm
Word Origin for blasto-
from Greek blastos; see -blast
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
before vowels blast-, word-forming element used in scientific compounds to mean "germ, bud," from Greek blasto-, comb. form of blastos "sprout, germ," of unknown origin.
Online Etymology Dictionary, © 2010 Douglas Harper
Bud; germ; budding; germination:blastocyst.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.