bill (n.1) Look up bill at Dictionary.com
"written statement," mid-14c., from Anglo-French bille, Anglo-Latin billa "list," from Medieval Latin bulla "decree, seal, sealed document," in classical Latin "bubble, boss, stud, amulet for the neck" (hence "seal;" see bull (n.2)). Sense of "account, invoice" first recorded c. 1400; that of "order to pay" (technically bill of exchange) is from 1570s; that of "paper money" is from 1660s. Meaning "draft of an act of Parliament" is from 1510s.
bill (n.2) Look up bill at Dictionary.com
"bird's beak," Old English bill "bill, bird's beak," related to bill, a poetic word for a kind of sword (especially one with a hooked blade), from a common Germanic word for cutting or chopping weapons (compare Old High German bihal, Old Norse bilda "hatchet," Old Saxon bil "sword"), from PIE root *bheie- "to cut, to strike" (source also of Armenian bir "cudgel," Greek phitos "block of wood," Old Church Slavonic biti "to strike," Old Irish biail "ax"). Used also in Middle English of beak-like projections of land (such as Portland Bill).
bill (v.) Look up bill at Dictionary.com
"to send someone a bill of charge," 1864, from bill (n.1). Related: Billed; billing.
bill (n.3) Look up bill at Dictionary.com
ancient weapon, Old English bill "sword (especially one with a hooked blade), chopping tool," common Germanic (compare Old Saxon bil "sword," Middle Dutch bile, Dutch bijl, Old High German bihal, German Beil, Old Norse bilda "hatchet." See bill (n.2).