1. adverb /ʌ.lɑŋˈsaɪd/
Along the side; by the side; side by side with.
Ahoy, bring your boat alongside of mine.
2. preposition /ʌ.lɑŋˈsaɪd/
Together with or at the same time.
The nurse worked alongside the doctor. <! material copied from Websters Revised Unabridged Dictionary (1913)
Wikipedia foundation.