Many are partly to entirely black, often with iridescence or bright markings of some sort. Most blackbird species form flocks at certain times of the year, and many form multispecies flocks. Blackbirds live in open habitats and eat seeds, grain, and insects.
The definition of a trepidation is a trembling movement, fear or nervousness. 1  An example of trepidation is when a speaker's hands are shaking due to nerves while giving a speech. 2  An example of trepidation is an anxious feeling before the first day of college.
Viscosity, a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In general terms it is the resistance of a liquid to flow, or its thickness.