placoid

/'plækɔid/

Thân thiện

A shark's skin is covered in small, rough placoid scales.

Definition

1. Adjective:
   • Resembling a plate or having plate-like structures: Used in zoology, particularly ichthyology, to describe a type of scale that is hard, flattened, and often tooth-like in structure.
   • Characterized by placoid scales: Pertaining to or covered with such scales, which are typical of cartilaginous fish like sharks and rays.

Usage Examples

• Adjective:
  • The shark's skin is covered in a rough, placoid texture.
  • Scientists studied the placoid denticles under a microscope.

Advanced Usage

• In scientific description: The term is primarily used in technical, biological contexts to classify and describe scale morphology.
  • The placoid scales, also called dermal denticles, provide hydrodynamic advantages.

Variants and Related Words

• Placoid scale (n): The specific scale type itself. This is a compound term listed separately.
  • Placoid scales are composed of dentine and enamel-like substances.

Synonyms

• Denticle: A small tooth-like projection, often used interchangeably with "placoid scale" in some contexts.
• Tooth-like: Descriptive of the shape and structure.

Notes on Meaning

• The word is highly specialized and is almost exclusively used in the field of zoology, specifically when discussing the integumentary system (skin and scales) of certain fish. It does not have common idiomatic or phrasal verb uses.

Học thuật

Adjective

1. as the hard flattened scales of e.g. sharks

Từ đồng nghĩa

• platelike