Wikia

Strangulate
Strangulate 30 yd range 1 min cooldown 1 Blood Instant Shadowy tendrils constrict an enemy's throat, silencing them for 5 sec. Non-player victim spellcasting is also interrupted for 3 sec.
Usable by
Class	Death knight
Properties
Type	Offensive
School	Shadow
Cooldown	1 min (GCD 1 sec)
Level required	58
Related debuff
Magic Strangulate Silenced. Duration: 5 sec
TCG image

“

I find your lack of faith disturbing.

”

Strangulate is a death knight ability learned at level 58. It uses a blood rune to silence the target for up to five seconds.

Modified by

2020

Glyph of Strangulate
Item Level 25Disenchants into:
Not disenchantable
Major Glyph
Classes: Death Knight
Requires Level 25
Use: Permanently teaches you this glyph.
Increases the Silence duration of your Strangulate ability by 2 sec when used on a target who is casting a spell.
Sell Price: 1

This is probably a tribute to Star Wars' Darth Vader, himself a dark, fallen warrior with mystic powers, who often used the Force to choke those who displeased him.
When tanking, this can be used to make a caster mob run into melee range with you.

Patch 5.2.0 (5-Mar-2013): Strangulate's cooldown has been reduced to 60 seconds (was 2 minutes).
Patch 3.3.0 (08-Dec-2009): Updated tooltip to include the functionality that this ability also interrupts spellcasting on NPCs.
Patch 3.2.0 (04-Aug-2009): This ability will also apply a 3 second interrupt effect against non-player controlled targets, making it more versatile against creatures immune to silencing effects.
Patch 3.1.0 (14-Apr-2009): No longer does damage and has been reduced to 1 rank.