Headlong
WordNet
adjective
(1) With the head foremost
"A headfirst plunge down the stairs"
"A headlong dive into the pool"
(2) Excessively quick
"Made a hasty exit"
"A headlong rush to sell"
adverb
(3) With the head foremost
"The runner slid headlong into third base"
(4) In a hasty and foolhardy manner
"He fell headlong in love with his cousin"
(5) At breakneck speed
"Burst headlong through the gate"