Pocket Heals

Your lifeline as a Tank or DPS in PvP. Usually performed by a very virtuous individual who understands that they must sacrifice their urge for pwnage to stand in the background and frantically avoid focused DPS.

We wouldn't have survived that tussle if it weren't for those clutch pocket heals!

Peach Heal

Used typically in context of Soulsborne/Souls-like games. A Peach Heal is the consumption of a healing item or material for a much smaller gain then it would be worth in order to play safer.
Peach heal has a different threshold for everyone, but most players would agree that healing with only 20%- 30% of your max health missing would be a Peach Heal.

Dumas: "You only need to use one flask charge to get back to 2 hits from death."
Toasty: "I use two just to be safe."
Dumas: "What a Peach Heal."