Formal:
* Verbose: This is the most formal and neutral term, simply meaning using more words than necessary.
* Prolix: Similar to verbose, but often implies a dull or tedious quality.
* Circumlocutory: This word emphasizes the roundabout or indirect way of speaking, avoiding directness.
* Logorrhea: This term suggests a tendency to talk excessively, often without much substance.
Informal:
* Windbag: This is a more informal and derogatory term, implying someone who talks a lot but says little of value.
* Motormouth: This refers to someone who talks constantly, often rapidly and without pause.
* Chatterbox: Similar to motormouth, but with a more playful connotation.
* Long-winded: This word suggests someone who speaks at length and often gets bogged down in details.
The best word to use depends on the specific context and the desired level of formality.