rec English
Noun
( en noun)
(informal)
 At 11:00, school’s out, and it’s time for rec
(informal) A recommendation or suggestion.
Verb
(informal) To recommend something such as a book, movie, product etc.

rel English
Preposition
( English prepositions)
(mathematics) Relative to.
* 1994 , N[ikita] Netsvetaev, "Diffeomorphism Criteria for Simply Connected EvenDimensional Manifolds", in, Oleg Viro, editor, Topology of Manifolds and Varieties , Advances in Soviet Mathematics [series] 18, [publisher], ISBN 0821841246, page 237,
 Since $M\_0$ and $M\_1$ are cobordant rel boundary and $f\_0,\; f\_1$ are n connected, the number $\backslash delta:=\backslash frac12(\backslash mathrm\{rk\}\; H\_nM\_0\backslash mathrm\{rk\}H\_nM\_1)$ is a nonnnegative integer.
* 1997 , Paul Selick, Introduction to Homotopy Theory , Fields Institute Monographs [series], [publisher], ISBN 0821806904, page 15,
 The following notations are in common use: $H:f\backslash simeq\; g$ (rel A'') means that ''H'' is a homotopy rel ''A'' from ''f'' to ''g ....
* 2002 , , Algebraic Topology ], [[w:Cambridge University Press, Cambridge] , ISBN 0521795400, page 355,
 Then in $n\backslash ge\; n\text{'}$, there is a map $h:Z\backslash to\; Z\text{'}$ such that $h,\; A=g$ and $gf\backslash simeq\; f\text{'}h$ rel' ''A'', so the diagram above is commutative up to homotopy '''rel ''A .
Anagrams
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