The Collaborative International Dictionary
Lignifying
Lignify \Lig"ni*fy\ (l[i^]g"n[i^]*f[imac]), v. t. [imp. & p. p. Lignified (l[i^]g"n[i^]*f[imac]d); p. pr. & vb. n. Lignifying (l[i^]g"n[i^]*f[imac]`[i^]ng).] [L. lignum wood + -fy: cf. F. lignifier.] (Bot.) To convert into wood or into a ligneous substance.
Wiktionary
lignifying
vb. (present participle of lignify English)