expression, adverb
to one's heart's content; as much as one likes; thoroughly
Adverbial expression meaning doing something fully, without holding back, until completely satisfied. Often used with verbs of eating, playing, talking, or enjoying.
休日は思う存分ゲームを楽しんだ。
On my day off, I enjoyed playing games to my heart's content.
思う存分食べてください。
Please eat as much as you like.