A rhythmic precursor to a syllable in birdsong

Any of a series of psychedelic drugs similar in structure to amphetamine and trimethoxyamphetamine.

Third-person singular simple present indicative form of know / (nonstandard) All persons, singular and plural, present form of know.

(of a document) That can, or that must be certified. / (informal, of a person) Mentally ill to such an extent that involuntary institutionalization is appropriate; crazy.