Standard Lemma guide

lightproof

adj · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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1

adj

Meaning 1

Sealed so that no light can enter.

Definition source: English Wiktionary via Wiktextract

Examples

  • Unexposed photographic film must be kept in a lightproof container or it will be exposed and ruined.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

adjective satellite

Meaning 2

not penetrable by light

Definition source: Princeton WordNet 3.0

Examples

  • lightproof containers

Meaning relationships

Synonyms: light-tight

Antonyms: none provided

History

Etymology

Etymology tree Proto-Indo-European *lewk-der. Proto-Germanic *leuhtaz Proto-West Germanic *leuht Old English lēoht Middle English light English light English -proof English lightproof From light + -proof.

Across languages

Translations

3 source translations are retained for this English entry.

  • Bulgarian: непрозра́чен (neprozráčen) — sealed so that no light can enter
  • Irish: solasdíonach — sealed so that no light can enter
  • Polish: światłoszczelny — sealed so that no light can enter