The Collaborative International Dictionary of English v.0.48:
Attenuate \At*ten"u*ate\, v. t. [imp. & p. p. Attenuated; p.
pr. & vb. n. Attenuating.] [L. attenuatus, p. p. of
attenuare; ad + tenuare to make thin, tenuis thin. See
1. To make thin or slender, as by mechanical or chemical
action upon inanimate objects, or by the effects of
starvation, disease, etc., upon living bodies.
2. To make thin or less consistent; to render less viscid or
dense; to rarefy. Specifically: To subtilize, as the
humors of the body, or to break them into finer parts.
3. To lessen the amount, force, or value of; to make less
complex; to weaken.
To undersell our rivals . . . has led the
manufacturer to . . . attenuate his processes, in
the allotment of tasks, to an extreme point. --I.
We may reject and reject till we attenuate history
into sapless meagerness. --Sir F.