As a noun tonner
is (in combination) a vehicle or other object having a specified tonnage, or weighing a specified number of tons.
As a proper noun conner is
from middle english connere, cunnere "inspector (of weighs and measures)".
tonner
English
Noun
(
en noun)
(in combination) A vehicle or other object having a specified tonnage, or weighing a specified number of tons.
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conner
English
Noun
(
en noun)
A marine European fish (); also, the related American cunner.