with open("fiveletterwords.txt") as f:
    lines = f.readlines()
    lines = [word.strip('\n') for word in lines]

lines[:10]

['aaron',
 'ababa',
 'abaci',
 'aback',
 'abaft',
 'abase',
 'abash',
 'abate',
 'abbey',
 'abbot']

frequencies = {}
for word in lines:
    for letter in word:
        if not letter in frequencies:
            frequencies[letter]=0
        frequencies[letter]+=1
frequencies = list(frequencies.items())
frequencies.sort(key=lambda x : x[1], reverse=True) 

frequencies[:10]

[('e', 3042),
 ('s', 2955),
 ('a', 2476),
 ('r', 1897),
 ('o', 1842),
 ('i', 1705),
 ('l', 1643),
 ('t', 1570),
 ('n', 1364),
 ('d', 1133)]

words = [word for word in lines if all(l in word for l, _ in frequencies[:5])]

words

['arose']