knur

[nur] /nɜr/
noun
1.
a knotty or hard protuberance or growth, as on a tree.
Origin
1350-1400; Middle English knorre, knor; cognate with Middle Low German, Middle Dutch, Middle High German knorre
British Dictionary definitions for knur

knur

/nɜː/
noun
1.
a knot or protuberance in a tree trunk or in wood
Word Origin
C16 knor; related to Middle High German knorre knot; compare knar