What is the meaning of conjunction?

noun

• The temporal property of two things happening at the same time.
  • usage: "the interval determining the coincidence gate is adjustable"
  • synonyms: concurrence, coincidence, co-occurrence
• The state of being joined together.
  • synonyms: junction, conjugation, colligation
• An uninflected function word that serves to conjoin words or phrases or clauses or sentences.
  • synonyms: conjunctive, connective, continuative
• The grammatical relation between linguistic units (words or phrases or clauses) that are connected by a conjunction.
• Astronomy) apparent meeting or passing of two or more celestial bodies in the same degree of the zodiac.
  • synonyms: alignment
• Something that joins or connects.
  • synonyms: junction