To awaken from sleep, to raise up, to cause to rise. In the NT, egeirō is the most common verb for resurrection — God raised Jesus from the dead. It appears in nearly every NT resurrection proclamation, from the angel at the tomb to Paul's letters.
The passive 'He was raised' (ēgerthē) is the earliest Christian creed (1 Corinthians 15:4). The passive voice is theological: Jesus didn't raise Himself — the Father raised Him, vindicating His sacrifice. 'God raised him from the dead' is the core apostolic proclamation in Acts. The same verb is used for raising the dead during Jesus' ministry (Jairus' daughter, Lazarus), prefiguring His own resurrection.