cartilaginous fishes having horizontally flattened bodies and enlarged winglike pectoral fins with gills on the underside; most swim by moving the pectoral fins
any of the stiff bony rods in the fin of a fish
a branch of an umbel or an umbelliform inflorescence
(mathematics) a straight line extending from a point
emit as rays; "That tower rays a laser beam for miles across the sky"
some situation or event that is thought about; "he kept drifting off the topic"; "he had been thinking about the subject for several years"; "it is a matter for the police"
the number of observations in a given statistical category
the ratio of the number of observations in a statistical category to the total number of observations
the number of occurrences within a given time period; "the frequency of modulation was 40 cycles per second"; "the frequency of his seizures increased as he grew older"