sirota

1. orphan
   Ostala je sirota sa pet godina. — She was orphaned at the age of five.
2. affect. (expressing pity) poor thing
   Sirota, ceo dan radi i niko joj ne pomaže. — Poor thing, she works all day and nobody helps her.

"Sirota" is both a noun and the feminine form of the adjective "sirot" ("poor, unfortunate, pitiable"): "sirota žena" – "poor, unfortunate woman". Sense 2 essentially coincides with this adjectival use. For an orphaned child, "siroče" is the usual word.