Ma'anar ƙamus na kalmar "sigina na telegraph" yana nufin hanyar sadarwa da ta ƙunshi watsa saƙonnin da aka rubuta a cikin dogon nesa ta hanyar amfani da tsarin telegraph. Yawanci ya ƙunshi amfani da siginonin lantarki don wakiltar haruffa, lambobi, ko wasu alamomi, waɗanda ake watsa su ta hanyar layin telegraph zuwa tashar karɓa. An yi amfani da siginonin waya da yawa kafin ƙirƙirar tsarin sadarwar zamani kamar tarho da intanet. Sau da yawa ana watsa siginar a matsayin jerin gajeru da dogayen bugun wutar lantarki, wanda aka sani da lambar Morse, wanda za'a iya yankewa a ƙarshen karɓa don sake gina ainihin saƙon.