Squish
mid 17th century: imitative.
wiktionary
Apparently an alteration of squash, influenced by obsolete squiss(“to squeeze”). Cognate with Scots squische, squies(“to crush, squeeze”). Compare also French esquicher from Old Occitan esquichar(“to squeeze, squish”). See also squeeze, squelch.
First possible attestation from 1999. Formed by analogy with crush and possibly smash, both of which have senses as types of compression as well as types of attraction. Later coined or recoined in 2007 by the user Raisin on the forums of the Asexual Visibility and Education Network as "a milder synonym for the word 'crush'". [1] The same term was used with a similar meaning in a 1997 episode of the TV show Aaahh!!! Real Monsters, [2] though the 2007 (re)coining was apparently independent. [1]
etymonline
squish (v.)
1640s, probably a variant of squash (v.), perhaps by influence of obsolete squiss "to squeeze or crush" (1550s). Related: Squished; squishing.
