'g' stands for something different every gRPC release:

• 1.0 'g' stands for 'gRPC'
• 1.1 'g' stands for 'good'
• 1.2 'g' stands for 'green'
• 1.3 'g' stands for 'gentle'
• 1.4 'g' stands for 'gregarious'
• 1.6 'g' stands for 'garcia'
• 1.7 'g' stands for 'gambit'
• 1.8 'g' stands for 'generous'
• 1.9 'g' stands for 'glossy'
• 1.10 'g' stands for 'glamorous'
• 1.11 'g' stands for 'gorgeous'
• 1.12 'g' stands for 'glorious'
• 1.13 'g' stands for 'gloriosa'
• 1.14 'g' stands for 'gladiolus'
• 1.15 'g' stands for 'glider'
• 1.16 'g' stands for 'gao'
• 1.17 'g' stands for 'gizmo'
• 1.18 'g' stands for 'goose'
• 1.19 'g' stands for 'gold'
• 1.20 'g' stands for 'godric'
• 1.21 'g' stands for 'gandalf'
• 1.22 'g' stands for 'gale'
• 1.23 'g' stands for 'gangnam'