The concept of "moth" in ASL is generally spelled upon first
usage and can be followed by the sign for "butterfly." From that
point on in the conversation if the person did the "butterfly" sign
it would be understood as meaning "the moth," "that moth."
If a story is being told about both "butterflies" and "moths" then
the BUTTERFLY sign would default to meaning "butterfly" and you
would fingerspell M-O-T-H.
I'm sure that if you asked "enough" people how to sign "MOTH"
eventually you'd come across a person who uses "Signed English" who
might tell you that the sign for "moth" is to do the sign for
"butterfly" but instead use "M" hands. I do not recommend you
do that. Sorry.
Next time I happen to come across my "Chinese Sign Language"
dictionary I'll have to check to see if it has a sign for MOTH.
(I've noticed that the Chinese seem to have a larger set of
established vocabulary for insects.)
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by Lifeprint.com © Dr. William Vicars