ubrzati

1. (+ acc.) to speed up; to accelerate
   Ubrzali smo korak jer je počela kiša. — We quickened our pace because it started raining.
   Nova aplikacija je ubrzala ceo proces. — The new app sped up the whole process.
2. (intransitive; ubrzati se) to speed up; to accelerate
   Vozač je naglo ubrzao na autoputu. — The driver suddenly accelerated on the motorway.
   Puls mi se ubrzao kad sam je video. — My pulse quickened when I saw her.

Perfective verb; the imperfective counterpart is ubrzavati.