means Yielding easily to pressure or touch; gentle, quiet, or lacking in hardness, harshness, or force.

from From Old English 'sōfte' (earlier 'sēfte'), meaning gentle, agreeable, or easeful — its oldest sense was less about texture than about comfort and mildness. It's a cousin of Old Saxon 'safti' and German 'sanft,' all tracing back to a Germanic root suggesting agreeableness and ease. The leap from 'pleasant' to 'squishy' came naturally: what soothes the senses tends to be what yields to the touch.