From spongebob. Mr. Krabs uses this phrase a few times throughout the episodes in the show. Basically means “what the heck”. Also can be used in place of “wow”.
*hears loud noise*

Neptune’s trousers!!! What was that?!

Neptune’s trousers!!! That cat got really high up in that tree!!!

What the Neptune’s trousers is going on here??
by Pipperoo October 14, 2017
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