There are many different types of cluster stitches your pattern should specify the type being used. For example, 3 tr cluster would be a cluster of three treble crochet stitches. dec = decrease, which is a technique used for shaping in crochet.dc = double crochet, which is one of the most common basic stitches in crocheting.That said, 'cl' refers generally to clusters. FL = 'front loop', also abbreviated FLO or 'front loop only', in contrast to BL/ BLO as described above.This is one of the taller basic crochet stitches, slightly taller than the standard treble crochet. Inc = increase, another technique used in shaping, just like decreasing (dec) is used.half dc or hdc = half double crochet, a basic crochet stitch in between the single crochet and double crochet in height.FP = front post, as compared to 'back post' described above.This term is not necessarily used in crochet patterns but it is a common abbreviation used among crafters when talking about their work online. incl = include / including / inclusive.oz = ounce/ounces, which is likely to be seen on yarn labels or in the portion of crochet patterns explaining how much yarn is needed.

This may be measured in other ways including grams (g), meters (m) or yards (yd). pc = popcorn, a textured crochet stitch similar to clusters and bobbles.

Images of abbreviations for words