jailbait
Synonym discussion
Sense: noun/1
Jailbait is not a neutral age word. It is insulting because it reduces a young person to sexual appeal while also pointing to legal danger for the adult involved. Minor and underage person are neutral legal descriptions and do not imply attraction at all. Teen is an everyday age label, but many teens are above the legal age in some places, so it is broader and less exact. Child is stronger and usually suggests someone younger than a teenager. In careful writing, people usually avoid jailbait and choose a neutral term instead. A news report might say a minor was exploited, not that the person was jailbait.
Common collocations
Etymology
Jailbait is a modern English slang compound built from jail and bait. The image is that being attracted to the person could lead someone into criminal trouble and prison. The word has long been used in a crude, objectifying way, which is why it is usually marked as offensive.