Listen
Old English hlysnan ‘pay attention to’, of Germanic origin.
wiktionary
From Middle English listenen, listnen, alteration (due to Middle English listen(“to listen, give heed to”)) of Old English hlysnan(“to listen”), from Proto-Germanic *hlusnijaną, *hlusnōną (compare Middle High German lüsenen), from Proto-Germanic *hlusēną (compare Old High German hlosēn), from Proto-Indo-European *ḱlew-(“to hear”) (compare Ancient Greek κλαίω(klaíō, “I make known, famous”), Welsh clywed(“to hear”), Latin clueō(“I am famous”), Lithuanian klausýti, Old Church Slavonic слѹшати(slušati, “to hear”), Sanskrit श्रोषति(śróṣati). Related to loud and German lauschen.
etymonline
listen (v.)
Old English hlysnan (Northumbrian lysna) "to listen, hear; attend to, obey" (transitive), from Proto-Germanic *hlusinon (source also of Dutch luisteren, Old High German hlosen "to listen," German lauschen "to listen"), from PIE root *kleu- "to hear."
This root is the source also of Sanskrit srnoti "hears," srosati "hears, obeys;" Avestan sraothra "ear;" Middle Persian srod "hearing, sound;" Lithuanian klausau, klausyti "to hear," šlovė "splendor, honor;" Old Church Slavonic slusati "to hear," slava "fame, glory," slovo "word;" Greek klyo "hear, be called," kleos "report, rumor, fame glory," kleio "make famous;" Latin cluere "to hear oneself called, be spoken of;" Old Irish ro-clui-nethar "hears," clunim "I hear," clu "fame, glory," cluada "ears;" Welsh clywaf "I hear;" Old English hlud "loud," hleoðor "tone, tune;" Old High German hlut "sound;" Gothic hiluþ "listening, attention."
The -t- probably is by influence of Old English hlystan (see list (v.2)). For vowel evolution, see bury. Intransitive sense is from c. 1200. To listen in (1905) was originally in reference to radio broadcasts.
listen (n.)
"an act of listening," 1788, in on the listen "alert," from listen (v.).
