[1] : The Collaborative International Dictionary of English v.0.48

macrospore \mac"rospore\, n. macro- + spore. bot.
   one of the specially large spores of certain flowerless
   plants, as selaginella, etc.
   1913 webster
see also:
selaginella 

[2] : WordNet (r) 2.0

macrospore
     n : larger of the two types of spore produced in heterosporous
         plants; develops in ovule into a female gametophyte syn:
          megaspore
see also:
megaspore 

Macrospore >> M Words
Macrospore, definition of term: Macrospore
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