GENERAL PATTERN NOTE TERMS:
[ ] work instructions within brackets as many times as directed
( ) work instructions within parentheses as many times as directed
* repeat the instructions following the single asterisk as directed
** repeat instructions between asterisks as many times as directed or repeat from a given set of instructions

Measurements
ā€ or in - inch(es)
cm - centimeter
g - gram or grams
m - meter
mm - millimeter
oz - ounce
yd(s) - yard)s)

US CROCHET TERMS

A

alt -   alternate

approx - approximately

B

beg - begin/beginning

bet - between

BL or BLO - back loop or back loop only

bo - bobble

BP - back post

BPdc - back post double crochet

BPdtr - back post double treble crochet

BPtr - back post treble crochet

BPhdc -back post half double crochet

BPsc - back post single crochet

BPtr - back post treble crochet

C

CC - contrasting color

ch - chain stitch

ch-sp - chain space / chain or space previously made  (ch-1 space)

CL - cluster

cont - continue

D

dc - double crochet

dc2tog - double crochet 2 stitches together

dc3tog - double crochet 3 stitches together

dec - decrease

dtr - double treble crochet

E

edc - extended double crochet

ehdc - extended half double crochet

esc - extended single crochet

etr - extended treble crochet

F

FL or FLO - front loop or front loop only

foll - following

FP - front post

FPdc - front post double crochet

FPdtr - front post double treble crochet

FPtr - front post treble crochet

FPhdc - front post half double crochet

FPsc - front post single crochet

FPtr - front post treble crochet

Fsc   foundation single crochet 

Fhdc  foundation half double crochet

Fdc foundation double crochet

G

gm - gram(s)

H

hdc - half double crochet

hdc2tog - half double crochet 2 stitches together

I

inc - increase

L

lp - loop

M

m - marker

MC - main color

P

patt - pattern

pc - popcorn stitch

pm - place marker

prev - previous

ps / puff - puff stitch

R

rem - remaining

rep - repeat

rnd - round

RS - right side

S

sc - single crochet

sc2tog - single crochet 2 stitches together

sh - shell

sk - skip

sl st - slip stitch

sm / sl m - slip marker

sp - space

st - stitch

T

tbl - through back loop

tch or t-ch - turning chain

tog - together

tr - treble crochet

tr2tog - treble crochet 2 stitches together

tr3tog - treble crochet 3 stitches together

trtr - triple treble crochet

W

WS - wrong side

Y

yo - yarn over