Extrapolate

[Michiko]

To [explain].

[Michiko]

To [bend] your leg, making an improvised vagina with the inside of [your knee], then you or a partner insert one or more fingers and [commence] finger-knee intercourse.

[exinilu]

To [release] your [manly](or [womanly]) fluids to gain pleasure.

[Tariq Zaki]

to extrapolate is a method of sex which is so crazy that some [consider it] the hardest [sex position] to master, but once [mastered] it is the most enjoyable.

[Couch Potatoe]

Extend the application of (a method or conclusion, especially one based on statistics) to an unknown situation by assuming that existing trends will continue or similar methods will be applicable.

[Mark Zuckerberg]

to guess or think about what might happen using information that is already known: