Correct spelling, explanation: both peer and pier are correct words, but they have different meanings and are used in different contexts. Peer refers to an equal, someone who is on the same level or status as another person. It can also refer to someone who belongs to the same age group or social group. A pier is a structure, often made of wood, concrete, or metal, that extends out into a body of water (like a sea, lake, or river) and is used for docking boats, ships, or for recreational purposes.

Definition of peer:
1. noun, a person who is the same age or has the same social position or the same abilities as other people in a group
The research paper was well-received by her academic peers, who praised the thoroughness of her analysis.
As a newcomer to the industry, she was eager to learn from her more experienced peers and gain insights into the field.
2. verb, to look carefully or with difficulty
She peered out of the window, trying to catch a glimpse of the rare bird that had been spotted in the garden.
The detective peered closely at the photograph, searching for any subtle clues that could help solve the mystery.

Collocations with peer:
Some most commonly used collocations include:
1. Peer pressure: the influence that a person’s peers or social group can have on their behavior, decisions, or actions.
She resisted peer pressure and made her own choices.
2. Peer review: the evaluation of scholarly or professional work by experts in the same field before it’s published or accepted.
The journal requires all submissions to undergo rigorous peer review.
3. Peer group: a group of individuals who are similar in age, status, interests, or social background.
He felt a strong sense of belonging within his peer group.
4. Peer relationship: the interaction and connection between individuals who are on the same level of age or status.
Her peer relationships play a significant role in her personal development.

Correct spelling, explanation: the choice between pier and peer depends on the context of your sentence. Use pier when you are referring to a structure that extends into a body of water, often for docking boats, ships, or for recreational purposes. Use peer when you are referring to an equal, someone who is on the same level or status as another person, or to describe the act of looking closely or attentively. Make sure to select the correct word based on what you want to convey.