As a native explained to me a long time ago
10以上 => 10 or more
10以下 => 10 or less
Inclusive .
these 10 include the number, if u want to exclude the number (Up to, as to speak) you use 未満 (みまん)
I can think of one more usage for 以下, which would be "The below", for instance:
薬は以下の説明書よく読んだ上で、ご使用下さい... (Use this medicine, after reading the instruction below carefully.)
説明書 せつめいしょーinstruction
ご使用 ごしようーuse
Thats as much as i can come up with when trying to think about the usages of these two words, any one with greater knowledge would be greatly appreciated, since im curious to know myself if I have been using these two words incorrectly myself :P.
Probably just an inconsistency in the dictionary that Jisho pulls from. They should be the same part of speech.
Difference in the part of speech between 以上 and 以下
Why is it that the word 以上 is marked as an "Adverbial noun, Temporal noun" but the word 以下 is marked just as a "Noun" despite being antonyms? Is there a difference in their usage I might be missing?
ありがとう!