length ‧ wise /ˈleŋθwaɪz/ BrE AmE ( also length‧ways /-weɪz/ British English ) adverb
[ Word Family: adverb : ↑ lengthwise , lengthways; adjective : lengthening, ↑ lengthy ; verb : ↑ lengthen ; noun : ↑ length ]
in the direction or position of the longest side:
Lay the bricks lengthwise.