wobbler n. (in California) a crime that can be charged as a misdemeanor or a felony. Editorial Note: This is a specific use of wobbler as it is more generally defined, “a thing or person that wavers, hesitates, or vacillates between two or more directions, options, or outcomes.” (source: Double-Tongued Dictionary)
In England there’s a phrase ‘to throw a wobbler’ which means ‘to get annoyed or upset’. As in: ‘He lost his job yesterday because he threw a wobbler when his boss told him off for being late.’