1Read じゅうぶん. Enough, sufficient, plenty — a required amount or degree is fully met, with nothing lacking. A na-adjective used as 十分だ / 十分な; also written 充分. The same spelling read じっぷん/じゅっぷん means "ten minutes."
これだけあれば十分だ。
This much is plenty.
彼にはこの仕事をこなす十分な実力がある。
He has more than enough ability to handle this job.
説明が十分でなかったので、質問が相次いだ。
The explanation wasn't sufficient, so questions kept coming.
2Adverb: to a sufficient degree — fully, thoroughly, well. Often in the form 十分に〜する.
試験前は十分に睡眠をとりなさい。
Get plenty of sleep before the exam.
内容は十分に理解できた。
I understood the content thoroughly.
安全を十分に確認してから作業を始める。
Begin work only after fully confirming that it's safe.
3(Rare/archaic) dividing into ten; a tenfold division (十分する). Seldom used in modern Japanese.
円周を十分して目盛りを刻む。
Divide the circumference into ten and mark off the scale.