headlong.1adv.He fell headlong, thit sé ar mhullach a chinn. He rushed headlong into the fight, chaith sé é féin ceann ar aghaidh isteach sa racán. 2a.aCeannrúideach. Headlong fall, titim f i ndiaidh mullaigh. bHeadlong flight, teitheadh scaollmhar, raon m maidhme.