A treble stitch. Assuming this is an American pattern, yoh twice, insert hook into next stitch, yoh and pull through stitch, yoh and pull through 2 loops on hook, yoh and pull through next 2 loops on hook, yoh and pull through remaining 2 loops on hook.
Yarn Over.
Slip Stitch
Probably "spaces". As in skip spaces.
I believe it means trail.
How am I supposed to know I’m asking the question here
yrn is the abbreviation for 'yarn' - the material you are knitting or crocheting with
Usually, rem would mean "remaining", as in, "for all remaining stitches" etc.
Travel
Snot
The meaning of TR on a bank account is asset based financing.
My grandmother loves crocheting.
It means decrease, usually by crocheting stitches together.