There are several synonyms for the word "tubes." Some of the most common include hoses, pipes, conduits, and cylinders. Hoses are typically used to transport liquids or gases, while pipes can refer to any kind of hollow cylindrical structure. Conduits are often used to protect or encase wiring, while cylinders are typically solid and can be used for storage or as part of an engine. Other synonyms for "tubes" include tubular structures, tubing, and chimneys. Whatever the intended use, there are many synonyms available to describe any kind of cylindrical or tubular object.