caustic - Sarcastic or severely critical, often in a hurtful or biting manner; or able to burn or corrode organic tissue, typically referring to chemicals or substances.
The caustic chemical spilled onto the floor and quickly started to eat away at the floor surface.
nook - Small area or space, like an alcove, that is conducive to meditating, reading, relaxing or quietly reflecting.
The alcove at the large window made a perfect nook, where Gemma could quietly take time away from the family, to read her book or write in her journal without interruption.