Pitiless, a. — Webster enters it under “pitiless”
1. Destitute of pity; hard-hearted; merciless; as, a pitilessmaster; pitiless elements.
2. Exciting no pity; as, a pitiless condition. -- Pit"i*less*ly, adv. -- Pit"i*less*ness, n.
Shades of meaning
Fernald lists pitilessness only as an antonym, under pity.
He lists it without comment; the entries above explain its neighbors.
Synonyms
none given