charger
Loading your saved state.
charger
An electronic device used to recharge the battery of another device, such as a smartphone, laptop, or camera, with electrical energy.
Ich habe mein Ladegerät für das Handy zu Hause vergessen.
I forgot my phone charger at home.
The word is clearly composed of the verb 'laden' (here in the sense of recharging) and the noun 'das Gerät' (device). So it is literally a 'Gerät zum Laden' (device for charging).
Ohne Ladegerät kann ich mein Tablet nicht mehr benutzen.
Without a charger, I can't use my tablet anymore.
'Ladegerät' (charger) belongs to the word family around 'laden' (to load/charge) and 'aufladen' (to recharge). The noun 'der Akku' (rechargeable battery, short for accumulator) is the typical object that is charged with a charger.
Der Akku ist fast leer, ich muss ihn mit dem Ladegerät aufladen.
The battery is almost empty; I have to charge it with the charger.
To say what the device is for, you use the preposition 'für' with the accusative. To say what you charge something with, you use 'mit' and the dative.
Hast du ein Ladegerät für ein iPhone?
Do you have a charger for an iPhone?
power supply
'Netzteil' and 'Ladegerät' both have to do with electricity for electronic devices. A 'Netzteil' supplies a device with the correct electrical voltage from a wall outlet. A 'Ladegerät' specifically recharges a battery, for example in a phone, laptop, or camera. The words can be confused because a charger often contains a power supply or looks like one. If the device is being powered directly by electricity, 'Netzteil' is often more precise. If it is about filling up a battery, 'Ladegerät' sounds more natural.
Am Wochenende habe ich mein Ladegerät bei meinen Eltern vergessen.
I forgot my charger at my parents' place over the weekend.
Im Kurs braucht sie morgen ein Netzteil für ihren kleinen Monitor.
In class tomorrow, she needs a power supply for her small monitor.