deep dive

Short definition from Wiktionary

Noun

1. 1
   An act of deep diving.
2. 2
   An in-depth examination or analysis of a topic.
3. 3
   Used other than figuratively or idiomatically: see deep, dive.
4. 4
   Alternative form of deep dive.

Verb

1. 1
   Alternative form of deep-dive.
2. 2
   To engage in deep diving.
3. 3
   To conduct an in-depth examination or analysis of a topic.
4. 4
   To involve to immerse oneself thoroughly in (something).