* "pitiful": Meaning full of pity, or deserving of pity.
* "pitiable": Meaning worthy of pity, or evoking pity.
* "pitifully": Meaning in a way that shows pity, or in a way that is pitiful.
* "pitiableness": Meaning the quality of being pitiful or deserving pity.
While not technically a suffix, "pity" is a root word used to create these related words.