leaf node
Technical term in graph theory and computer science for a node with no children. The English gloss 'leafnodes' is a plural form; the Japanese term is singular/plural neutral.
In a binary tree, a leaf node is a node that has no children.
Compound of 葉 (は, 'leaf') and 節点 (せってん, 'node'), a calque of English 'leaf node'. The reading はせってん follows standard on'yomi for the kanji.