The company name Nabla Ltd. comes from the mathematical symbol commonly used in the equations we solve using the OpenFOAM software. The Oxford English Dictionary definition
of ‘nabla’ reads:
Pronounciation
’nęble
Etymology
ad. L. nablum (Vulg.; nablium, Ovid) a. Gr. , prob. of Phœnician origin, and so identical with Heb. nbel which it is used to translate
Definition
A name of a symbolic operator , defined as . The operator was introduced by Sir William Hamilton, who represented it by the symbol
. (In quot. 1837 he uses as a symbol for any arbitrary function.)
Quotations
1837 W. R. HAMILTON in Trans. R. Irish Acad. XVII. 236 Considering as a function of a new variable and performing any operation
with reference to the latter variable, .
1846 Proc. R. Irish Acad. III. 291 The following. . . general characteristic of operation , in which , , are ordinary rectangular
coordinates, while , , are his [sc. Hamilton’s] own coordinate imaginary units, appears to him to be one of great importance in many researches.
1847 W. R. HAMILTON in Phil. Mag. XXXI. 291 In the paper designed for Southampton. . . the characteristic was written ; but this more common sign
has been so often used with other meanings, that it seems desirable to abstain from appropriating it to the new signification here proposed.
1853 -- Lect. Quaternions vii. 610 Introducing, for abridgment, as a new characteristic of operation, a symbol defined by the formula etc. . . .
1884 W. THOMSON Notes Lect. Molecular Dynamics & Wave Theory of Light at John Hopkins Univ. x. 112 (MS.), I took the liberty of asking Professor
Bell. . . whether he had a name for this symbol ; and he has mentioned to me nabla, a humorous suggestion of Maxwell’s. It is the name of an Egyptian harp,
which was of that shape.
1892 Phil. Trans. R. Soc. CLXXXIII. 431 Physical mathematics is very largely the mathematics of . The name Nabla seems, therefore, ludicrously inefficient.
1939 D. E. RUTHERFORD Vector Methods iv. 50 A convenient method of writing is , where (pronounced ‘nabla’) is defined as the vector
operator
1969 L. YOUNG Systems of Units in Electr. & Magn. v. 63 The symbol nabla, , is a vector differential operator.
, prob. of Phœnician origin, and so identical with Heb. 
, defined as 
. The operator was introduced by Sir William Hamilton, who represented it by the symbol
. (In quot. 1837 he uses 
as a symbol for any arbitrary function.)
as a function 
of a new variable 
and performing any operation 
.
, in which 
, 
are ordinary rectangular
coordinates, while 
, 
, 
are his [sc. Hamilton’s] own coordinate imaginary units, appears to him to be one of great importance in many researches.
; and he has mentioned to me nabla, a humorous suggestion of Maxwell’s. It is the name of an Egyptian harp,
which was of that shape.
is 
, where 