アルカリ性

• Reading: アルカリせい
• Romaji: arukarisei
• Kanji breakdown: 性 (sei) — nature, property, characteristic
• Pronunciation: /a.ɾɯ.ka.ɾi.seː/

Meaning

Alkalinity; alkaline nature. The chemical property of being alkaline (having a pH above 7).

A noun and no-adjective combining the loanword アルカリ (arukari, alkali, from Dutch/Portuguese) with 性 (sei, nature/property). Used in science, health, and daily life contexts. Paired with 酸性 (sansei, acidity) as its opposite. Common in discussions about water quality, food, soil, and cleaning products.

Examples

1. この温泉はアルカリ性で肌がすべすべになる。 This hot spring is alkaline, which makes your skin smooth.
2. アルカリ性の洗剤は油汚れに効果的です。 Alkaline detergent is effective against grease stains.
3. リトマス紙が青くなったのでアルカリ性だと分かった。 The litmus paper turned blue, so we knew it was alkaline.

Usage Guide

Context: science, health, cleaning, cooking

Tone: informational

Origin & History

アルカリ comes from the Arabic al-qaly (plant ashes) via Dutch or Portuguese during the Edo period. Combined with the Sino-Japanese suffix 性 (sei, nature/property) to describe the chemical characteristic.

Cultural Context

Era: Modern

Generation: All ages

Social background: Universal