Deuce the Caboose 

Inserting two fingers into the anal cavity, then spread your fingers apart like your saying peace.

You can ease a woman into anal if you slowly deuce the caboose

Deuce the Caboose by beatboxboy21 March 18, 2021

Deuce in the Caboose

To defecate in one's drawers. Typically used to affectionately refer to a toddler pooping in their diapers. Adults see the droopy diaper from behind the toddler, or the caboose / rear-end.

Refer to related phrases: drop a deuce, deuce

Ohhhh, how cute! Your toddler is waddling away from the table...wait a minute! There appears to be a 'deuce in the caboose' of theirs!

Deuce in the Caboose by HeavyD in CH April 21, 2011