protoxylem

[proh-tuh-zahy-luh m, -lem] /ˌproʊ təˈzaɪ ləm, -lɛm/
noun, Botany
1.
the part of the primary xylem that develops first, consisting of narrow, thin-walled cells.
Origin
1895-1900; proto- + xylem
Examples from the web for protoxylem
  • During internode elongation only protoxylem vessels stained for the presence of lignin.
British Dictionary definitions for protoxylem

protoxylem

/ˌprəʊtəˈzaɪləm/
noun
1.
the first-formed xylem tissue, consisting of extensible thin-walled cells thickened with rings or spirals of lignin Compare metaxylem
protoxylem in Science
protoxylem
  (prō'tə-zī'ləm)   
The first formed xylem that differentiates from the procambium.