definition of
[underline]

[1] #1 underline v. [underscore, emphasize, emphasise] give extra weight to (a communication); "Her gesture emphasized her words". wn

[2] #2 underline n. [underscore] a line drawn underneath (especially under written matter). wn

[3] #3 underline v. [underscore] draw a line or lines underneath to call attention to. wn