Anapestic tetrameter is a rhythm for comic verse, and prominent examples include Clement Clarke Moore's "A Visit from St. Nicholas" and the majority of Dr. Seuss's poems. When used in comic form, anapestic tetrameter is often highly regular, as the regularity emphasizes the breezy, melodic feel of the meter, though the initial unstressed beat of a line may often be omitted.
An iamb is a metrical foot that consists of an unstressed syllable followed by a stressed one—daDUM. Penta- means five. Meter refers to a regular rhythmic pattern in poetry. So iambic pentameter is a kind of rhythmic pattern that consists of five iambs per line, almost like five heartbeats: daDUM daDUM daDUM daDUM daDUM.
Definition of Spondee. A metrical foot, spondee is a beat in a poetic line that consists of two accented syllables (stressed/stressed) or DUM-DUM stress pattern. Spondee is a poetic device that is not as common as other metrical feet, like iamb and trochee.