To careen is defined as to move quickly and wildly from side to side in a specific direction in an out of control manner.(verb)
When you lose control of a sled and start going rapidly downhill in an uncontrolled way, this is an example of a time when you careen down the hill.
See careen in Webster's New World College Dictionary
Origin: Fr carener, careen < OFr carène, carine < OIt carena < L carina, keel of a ship, orig., nutshell: see hard
See careen in American Heritage Dictionary 4
verb ca·reened, ca·reen·ing, ca·reens verb, intransitive
Origin: From French (en) carène, (on) the keel
Origin: , from Old French carene
Origin: , from Old Italian carena
Origin: , from Latin carīna; see kar- in Indo-European roots.
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