Collins COBUILD Advanced Learner's English Dictionary - underscore

(underscores, underscoring, underscored) 1. If something such as an action or an event underscores another, it draws attention to the other thing and emphasizes its importance. (mainly AM; in BRIT, usually use underline) The Labor Department figures underscore the shaky state of the economic recovery... = underline VERB: V n, also V that, V the fact that 2. If you underscore something such as a word or a sentence, you draw a line underneath it in order to make people notice it or give it extra importance. (mainly AM; in BRIT, usually use underline) He heavily underscored his note to Shelley. = underline VERB: V n