What is a pickle
Dictionary definitition: A small cucumber preserved in vinegar, brine, or a similar solution.
Yes, per dictionary pickle is food preserved in brine or vinegar. Pickles are a staple in Indian cuisine. Here it is an intensely flavored condiment served with meals to create a balance of flavor (pickles are prepared in a range of flavors from sour and spicy to sweet). This condiment also acts as appetite stimulant and digestive aid.
There are pickles and then there are pickles (unless you are looking at the rubric for this food52 feature). Cucumbers can be pickled but not all pickles are cucumbers. Kimchi is a pickle,actually even sauerkraut if you think about it. Pickles abound around the globe.
Alternatively, to be "in a pickle" is to be in a situation in which you are not quite sure of the, um, solution. As in "I did not add enough salt to my brine....how will that affect lacto-fermentation? Will my pickles pickle?"