/ ˈpleɪnli; NAmE / adverb
1.
in a way that is easy to see, hear, understand or believe
SYN clearly :
The sea was plainly visible in the distance.
The lease plainly states that all damage must be paid for.
She had no right to interfere in what was plainly a family matter.
Plainly (= obviously) something was wrong.
2.
using simple words to say sth in a direct and honest way :
To put it plainly, he's a crook.
3.
in a simple way, without decoration :
She was plainly dressed and wore no make-up.