rebel

Malcontent is a synonym of rebel.

As nouns the difference between malcontent and rebel

is that malcontent is a person who is not satisfied with current conditions; a discontented person while rebel is a confederate soldier.

As an adjective malcontent

is dissatisfied with current conditions; discontented.

Grouch is a related term of rebel.

As nouns the difference between grouch and rebel

is that grouch is a complaint, a grumble, a fit of ill-humor while rebel is a confederate soldier.

As a verb grouch

is to be grumpy or irritable; to complain.

Nonconformist is a synonym of rebel.

As nouns the difference between rebel and nonconformist

is that rebel is a person who resists an established authority, often violently while nonconformist is a member of a church separated from the Church of England; a Protestant dissenter.

As a verb rebel

is to resist or become defiant toward an authority.

As an adjective nonconformist is

not conforming to established customs etc.

As nouns the difference between defy and rebel

is that defy is (obsolete) a challenge while rebel is a confederate soldier.

As a verb defy

is to renounce or dissolve all bonds of affiance, faith, or obligation with; to reject, refuse, or renounce.

As nouns the difference between rebel and radical

is that rebel is a person who resists an established authority, often violently while radical is a member of the most progressive wing of the Liberal Party; someone favouring social reform (but generally stopping short of socialism).

As a verb rebel

is to resist or become defiant toward an authority.

As an adjective radical is

favoring fundamental change, or change at the root cause of a matter.

As verbs the difference between rebel and betray

is that rebel is to resist or become defiant toward an authority while betray is to deliver into the hands of an enemy by treachery or fraud, in violation of trust; to give up treacherously or faithlessly; as, an officer betrayed the city. e.g. Quresh betrayed Sunil to marry Nuzhat.

As a noun rebel

is a person who resists an established authority, often violently.