The O'Neil Family Motto: "lamh dearg eirin"  (The Red Hand of Ireland) BLAZON OF ARMS - Argent, two lions rampant combatant gules, supporting a dexter hand couped at the wrist of the last, in chief three estoiles of the second, in the base waves of the sea, therein naitant a salmon all proper.
Various family spellings are Naill, Naille, Neal, Neale, Neale, Neall, Nealle, Neil, Neill, O'Neil, O'Neill, O'Neal, O'Neale, O'Neail, O'Neall, O'Nealle, MacNeil, MacNeill, MacNeal, MacNeall, MacNealle. The "Mac" is found abreviated to "Mc" and all of the "O'" variations are also found without the apostrophe. The two main prefixes are Mac (Mc) meaning "son of" and O' (Ó) meaning "grandson of". The O' (Ó) eventually became to mean further male decendants.
Interesting links to visit
O'Neil History           Irish History           Naill of the Nine Hostages           Shane's Castle Ireland History in Maps         The O'Neil Genealogy Information Sharing Network