English Reference
Verb

intensify

v.
C1 Advanced Oxford US /ɪnˈtɛnsəˌfaɪ/ UK /ɪntˈɛnsɪfˌaɪ/ in·ten·si·fy UK spelling intensified, intensifies, intensifying

v.to become stronger or more serious, or to make something do so. You use this when a feeling, a sound, or a situation gets much more powerful.

v.to increase in degree, strength, or magnitude; to make something more intense. Functions as both a transitive and intransitive verb.


SIMPLE

The rain began to intensify as the sun went down.

CONTEXTUAL

The police decided to intensify their search for the missing hiker after finding a backpack near the river.

COMPLEX

Diplomatic efforts to resolve the border dispute are expected to intensify over the coming weeks as both nations face mounting pressure from the international community.

Usage

Can be used intransitively (the storm intensified) or transitively (they intensified their efforts).

Pitfall
The noise was intensified by the timeThe noise intensified over time

Learners often use the passive voice for natural processes that are better described using the intransitive active form.

Usage intensifying campaign · intensified since

The 2026 K League season started on February 28 and is due to finish on December 6, but in the current climate, calls to move the traditional schedule have intensified.

Al Jazeera· 14 Aug 2026

Her daughter’s seizures have intensified since the move, she sleeps on the floor and Huda is painfully blunt: “My daughter is dying slowly.” Antiracist protesters outside the Bell in July 2025.

The Guardian· 13 Aug 2026

Common in science writing


From intense + -ify. Compare French intensifier.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C1 · Advanced
Frequency Occasional
Updated