وَالْمَلَائِكَةُ جَمْعُ مَلَكٍ
Malāʾikah is the plural of malak, an angel.
Classical lexicographers connect the word to alūkah, a message or mission, while also discussing alternative morphological derivations. This suits angels' role as messengers, but etymology alone cannot demonstrate everything about their nature.
The vocalization also distinguishes malak (angel) from malik (king). The similarity of spelling or sound does not permit two different meanings to be merged.