でたらめ出鱈目detarameデタラメdetarame
1.

A state of being characterized by statements or actions that lack consistency with reality or logical coherence, often suggesting carelessness or deceit.

2.

Describes a person or behavior that is unreliable and not trustworthy, indicative of a casual or frivolous approach to important matters.

3.

Refers to nonsensical remarks or claims that are made without grounding in fact, often used to dismiss absurd or ridiculous assertions.

Example:

彼はでたらめな約束をして彼女を誘惑した。