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REFERENCE

solid

adj. · n.
US //ˈsɑɫəd// UK //sˈɒlɪd// sol·id
  1. 1 firm and hard (adj.)
    A2 Elementary Science

    firm and hard; not a liquid or a gas.

    having a firm and stable shape; not liquid or gaseous.

    Example

    Water turns into solid ice when the temperature drops below freezing.

    Example

    The chemist explained that at room temperature, the element remains a solid rather than transitioning into a liquid state.
  2. 2 not hollow (adj.)
    B1 Intermediate

    made of the same material all the way through, with no holes or empty space inside.

    not hollow or containing gaps; consisting entirely of a specific substance throughout its volume.

    Example

    The door was made of solid oak, making it very heavy and strong.

    Example

    The sculpture was carved from a solid block of marble, ensuring there were no structural weaknesses or internal fissures.
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  1. 3 reliable or good (adj.)
    B2 Upper Intermediate

    reliable, dependable, or of good quality.

    dependable and of high quality; providing a sound basis for trust or further action.

    Example

    She gave a solid performance in the play and the audience loved her.

    Example

    The researcher provided solid evidence to support her theory, convincing even the most skeptical members of the board.
  2. 4 continuous (adj.)
    B2 Upper Intermediate

    without any gaps or interruptions.

    continuous in time or space; without breaks or punctuation.

    Example

    The rain continued for three solid days, causing the river to overflow.

    Example

    He worked for eight solid hours without a break to ensure the project was finished before the deadline.
  3. 5 one color (adj.)
    B1 Intermediate

    having only one color all over, without any patterns or stripes.

    of a single uniform color throughout; lacking patterns, stripes, or variegation.

    Example

    I prefer wearing solid colors like blue or black rather than busy patterns.

    Example

    The interior designer recommended solid curtains to balance the intricate floral wallpaper in the master bedroom.
  4. 6 state of matter (n.)
    B1 Intermediate Science

    a substance that stays in the same shape and does not flow like a liquid.

    a substance in a physical state characterized by structural rigidity and resistance to changes in shape or volume.

    Example

    The teacher asked the students to list three examples of solids found in the classroom.

    Example

    In physics, a solid is defined by its ability to maintain a fixed volume and shape regardless of its container.
  5. 7 a favor (n.)
    C1 Advanced Informal Slang

    a helpful act or a favor for someone.

    a favor or helpful act performed for another person.

    Example

    Could you do me a solid and watch my dog while I go to the store?

    Example

    He asked his colleague to do him a solid by covering his shift on Friday afternoon.

    Usage

    Usually used in the phrase 'do someone a solid'.
Etymology 1

From Middle English solide, borrowed from Old French solide, from Latin solidus (“solid”), from Proto-Indo-European solh₂-i-dʰ-o-s (“entire”), suffixed form of root solh₂- (“integrate, whole”). Doublet of sol, sold, soldo, solidus, sou, and xu.

Etymology 2

From Middle English solid, from the adjective, Middle French solide, or Latin solidum. Doublet of solidum.

Word family

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