plural dels
mathematics
: an operator (see operator sense 3a) upon a function of three variables (as x, y, and z) interpreted as coordinates in a right-handed rectangular system for obtaining the partial derivatives of the function, for multiplying these derivatives by the unit vectors (as I, J, K) along the axes, and for adding the results
The vector differential operator ∇ (often called del) is the mathematical operator which determines how much vectors change in each of their 3 spatial components.Rhodri Evans
often used before another noun
We will soon see that the dot and cross products between the del operator and a vector also define useful operations.Markus Zahn

del

2 of 4

abbreviation (1)

1
delegate; delegation
2
delete

Del

3 of 4

abbreviation (2)

Delaware

del.

4 of 4

Latin abbreviation

Word History

Etymology

Noun

probably as abbreviation for delta entry 1

First Known Use

Noun

1901, in the meaning defined above

Time Traveler
The first known use of del was in 1901

Browse Nearby Words

Cite this Entry

“Del.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/del. Accessed 26 Aug. 2026.

Medical Definition

del

abbreviation
delusion
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