Incorrect spelling

atleast

Incorrect spelling, explaination: atleast is incorrect, because it is not one word, but two (at and least), that create a phrase. Therefore we should also wrote them separately: at least.


Correct spelling

at least

Correct spelling, explaination: at least is the correct form, because it is a phrase (at + least), not one word. Sometimes also at the least, this phrase means that something is absolute minimum; at the lowest possibility; meaning also in any case. These two words, as a phrase, are also spelled separately, so atleast is incorrect.

Definition of at least:
1. phrase, at the lowest possible number or quantity
You should pay in advance for at least one night of stay in this hostel.
2. phrase, anyhow, despite problems
You could at least call me before you came!