1. Adverb (fukushi)

   to one's heart's content; as much as one wants; as hard as one can; with all one's strength; to the best of one's ability; to the utmost; with determination; hard; heavily

   see 思い切り

2. Noun

   resolution; decisiveness; determination; resignation

   see 思い切り

Also written 思いっ切り【おもいっきり】omoikkiri