� adipose fin � a small rayless fleshy lobe located on the back between the dorsal fin and tail (sometimes absent if this fin has been clipped during a biological study).
� anal fin � a prominent, unpaired fin located on the mid-line of the underside of the fish near the tail.
� barbel � a fleshy process (whisker-like) found near the mouth.
� caudal fin � the tail fin.
� caudal peduncle � the narrowest part of the body; located between the anal fin and the caudal (tail) fin.
� compressed � in reference to the body flattened from side to side.
� ctenoid scales � scales that feel rough and have tiny spines (teeth) along their outside edge.
� cycloid scales � scales that feel smooth, have no spines, and are somewhat round in shape.
� dorsal fin(s) � prominent, unpaired fin or fins located on the mid-line of the back of the fish.
� fin rays � supports (lines) in the fin holding the membrane.
� gill cover � the flap (large thin bones) that cover the gills on each side of the head.
� haloes � the pale or bluish ring around spots on the sides of some fish.
� maxilla � the bone of the upper jaw ('lip') extending back from the tip of the mouth ('nose').
� paired fins � matched fins (one of each side of the body) located toward the sides near the gill area (pectoral fins) or ventral area near the head or further back on the belly (pelvic fins).
� pectoral fins � paired fins ('arms') located on the sides near the gill area.
� pelvic fins � paired fins ('legs') located below or behind the pectoral fins.
� snout � the part of the head ('nose') in front of the eyes.
� soft rays � fin rays that are usually branched and flexible.
� spine � fin rays that are not branched, and are usually stiff and sharp.
� subterminal mouth � a mouth where the upper jaw projects forward in front of the lower jaw so that the mouth points somewhat downward.
� terminal mouth � a mouth where both the lower and upper jaw project in front of the snout so that the mouth points forward.
