Primus has multiple meanings, generally derived from the Latin word meaning 'the first one'.

• For campers' and soldiers' liquid-hydrocarbon primus stoves see portable stove#history.
• For the Swedish manufacturer of such stoves and other outdoor gas- or liquid-fueled heating and lighting devices, see Primus AB .
• For the rock band, see Primus (band).
• For the presiding bishop of the Scottish Episcopal Church, see Primus of Scotland
• For the presiding bishop of the Norwegian Lutheran State Church , see Primus of Norway
• For the fictional god in some Transformers animation or comic plots, see Primus (Transformers).
• For the 2nd-century Coptic patriarch, see Primus of Alexandria.
• For the 19th-century painter, see Nelson Primus .
• Singapore's 155mm Self-propelled Howitzer SSPH Primus
• Primus Knowledge Solutions, Inc. registered the name "Primus" in 1997 along with SolutionBuilder, SolutionExplorer, and SolutionPublisher to identify their line of eServer Knowledgebase products. Primus Knowledge Solutions was purchased by ATG in early 2005.