/bəˈsɪləs/

noun

An elongated rod shaped cell, which is more elongated than a coccobacillus cell and less elongated than a filamentous cell (see coccobacillus and filamentous). A bacillus can also have rounded, squared (B. anthracis) or tapered ends  (see fusiform). Many bacillus shaped cells resemble a cylinder whose length/width ratio is greater than two. However, not all bacilli (p.) are limited to this description; bacilli can differ considerably in their length to width ratio and end shape. Curved rod shapes are often classified under the term "vibrio" which represents its own distinct shape  (see vibrio). short rounded or swollen rod shaped cells can be classified as coccobacilli (see coccobacillus). Not to be confused with Bacillus (representing the taxon).

New Latin, from Latin baculum