mouse: any of numerous small rodents typically resembling diminutive rats having pointed snouts and small ears on elongated bodies with slender usually hairless tails
mammal: any warm-blooded vertebrate having the skin more or less covered with hair; young are born alive except for the small subclass of monotremes and nourished with milk
arabidopsis thaliana: a small invasive self-pollinating weed with small white flowers; much studied by plant geneticists; the first higher plant whose complete genome sequence was described