retarder bedeutet auf Englisch

delay [delayed, delaying, delays]▼◼◼◼(to put off until a later time)
verb
[UK: dɪ.ˈleɪ] [US: də.ˈleɪ]My flight was delayed. = Mon vol a été retardé.

stall [stalled, stalling, stalls]▼◼◼◻(to employ delaying tactics against)
verb
[UK: stɔːl] [US: ˈstɒl]

obstruct [obstructed, obstructing, obstructs]▼◼◼◻(To impede, retard, or interfere with)
verb
[UK: əb.ˈstrʌkt] [US: əb.ˈstrəkt]

set back▼◼◻◻(delay)
verb
[UK: set ˈbæk] [US: ˈset ˈbæk]