/ ˌʌndəˈlaɪn; NAmE -dərˈl-/ (also under·score especially in NAmE ) verb
1.
[ vn ] to draw a line under a word, sentence, etc.
2.
to emphasize or show that sth is important or true :
[ vn ]
The report underlines the importance of pre-school education.
[ v wh- ]
Her question underlined how little she understood him.
[also v that ]