Many years ago there was a software with that name (Sidekick, released in 1984 by Borland ). It was a personal Manager of information (PIM: personal information manager ) a programme of support that was used when you were working and needed quick help ( calendar editor, personal texts, calculator, ASCII Codes, directory of 41 email accounts; Later expanded the possibilities of assistance with other benefits that were added ).I understood sidekick * as that side kick who used to give us our classmates for ayudásemos them, e.g., with the answer to a test question. But if I feel that words that have been identified here, as partner, buddy, etc., respond to the spirit, reason, purpose, direction and sense of that software.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list