Definition of prothallus
1 : the gametophyte of a pteridophyte (as a fern) that is typically a small flat green thallus attached to the soil by rhizoids
2 : a greatly reduced structure of a seed plant corresponding to the pteridophyte prothallus
Origin and Etymology of prothallus
First Known Use: 1854
Rhymes with prothallus
Seen and Heard
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