Onion
An onion was an Earth vegetable with a thin, paper-like skin and a structure of tightly-packed concentric rings that were usually segmented during preparation for eating or cooking.

In 1986, Doctor Gillian Taylor ordered a mushroom and pepperoni with extra onions pizza at an Italian restaurant. ()

Based on Dr. Phlox's prior comments, Jonathan Archer surmised that the closest thing Denobulans had to pets were "furry little things that [went] well with onions." ()

On the dinner table conjured by Korob for Kirk, Spock and McCoy in 2267 was a bowl of white onions. ()

In 2371, the farmer's daughter's root cellar contained onions. ()

While operating on Seven of Nine, The Doctor commented that removing her Borg implants was like peeling an onion. ()

See also 
Felada onion crisp
French onion soup
Green onion
Green onion dipping sauce
Grilled curled onions
Onion rings
Onion soup
Shallot

External link
 

de:Zwiebel
Earth foods
Earth plants