The Proto-Indo-European word *kl̥hₓ-ro-s
Word *kl̥hₓ-ro-s
Meaning plank
See also Proto-Indo-European: *kel- ‘hew, strike’
Synonyms *bʰélhaĝs, *plut-, *swel-~sel-

Comments
Mallory J.P. and Adams D. (2006)

Other words that might be of interest
*skéits ‘shield, board’