is mainlining

• present progressive

  present progressive

  Used to describe an ongoing action or state that is currently taking place in the immediate present.

  of mainline (3rd person singular).
  mainline

  verb (used without object)

  to inject a narcotic, especially heroin, directly into a vein.

Related Words

• dominant
• key
• leading
• main
• major
• outstanding
• paramount
• predominant
• preeminent
• primary
• prime
• prominent