an environmental cue, as the length of daylight or the degree of temperature, that helps to regulate the cycles of an organism's biological clock

confused, incoherent, foolish, or meaningless talk

to make favorably inclined; appease; conciliate

having a ready insight into and understanding of things

pertaining to or of the nature of a spasm; characterized by spasms

unmoved by persuasion, pity, or tender feelings; stubborn; unyielding

a defense especially of one's opinions, position, or actions

young, new, or inexperienced