šaputati

1. to whisper
   Deca su šaputala da ne probude bebu. — The children were whispering so as not to wake the baby.
   Šaputao joj je nešto na uvo. — He was whispering something in her ear.
2. formal (of leaves, wind) to rustle; to murmur
   Lišće je tiho šaputalo na vetru. — The leaves rustled softly in the wind.

The person whispered to is in the dative: šaputati nekome.