naboj

1. (emotional) charge; tension
   Film ima snažan emotivni naboj. — The film carries a strong emotional charge.
   Između njih dvojice postoji neki naboj. — There's some tension between the two of them.
2. (in physics) charge
   Elektron ima negativan naboj. — An electron has a negative charge.
3. (explosives, firearms) explosive charge; propellant charge
   Rudari su postavili eksplozivni naboj u stenu. — The miners placed an explosive charge in the rock.

In physics Serbian more often uses naelektrisanje; for 'cartridge' the usual word is metak.