-eth1

1.
an ending of the third person singular present indicative of verbs, now occurring only in archaic forms or used in solemn or poetic language: doeth or doth; hopeth; sitteth.
Also, -th.
Origin
Old English -eth, -ath, -oth, -th; akin to Latin -t

-eth2

1.
variant of -th2 , the ordinal suffix, used when the cardinal number ends in -y: twentieth; thirtieth.
British Dictionary definitions for -eth

-eth1

suffix
1.
forming the archaic third person singular present indicative tense of verbs: goeth, taketh
Word Origin
Old English -eth, -th

-eth2

suffix
1.
a variant of -th2 twentieth

-th2

suffix
1.
forming ordinal numbers: fourth, thousandth
Word Origin
from Old English -(o)tha, -(o)the