Although you can accurately call the person who cuts your hair your "trichologist" if you want to, the term is usually applied as it is in our example sentence: to someone who studies and treats hair and scalp ailments. The "trich" in "trichologist" is the Greek "trich-," stem of "thrix," meaning "hair." This root makes an appearance in a number of other similarly technical-sounding words, such as "trichiasis" ("a turning inward of the eyelashes often causing irritation of the eyeball"), "trichome" ("an epidermal hair structure on a plant"), and "trichotillomania" ("an abnormal desire to pull out one's hair").
I am not aware of any hairdressers mentioned in the Bible, however, there are a few things that come to mind in relation to this word.
The hairs of your head
"Are not two sparrows sold for a cent? And yet not one of them will fall to the ground apart from your Father. But the very hairs of your head are all numbered. So do not fear; you are more valuable than many sparrows.
Hairdressers and scalp specialists can rejoice in knowing that the Lord their G-d is a hair expert. He made it and watches over the hairs of our head.
There is, of course, the story of Samson and his hair (Judges 16). Samson's hair was uncut because he was placed under a Nazarite vow by G-d (Judges 13:4-5). The processes involved in the vows of a Nazarite (Numbers 6:2) are explained in Numbers 6.
Paul of Tarsus also took the vows of Nazarite (Acts 18:18) and honored them for several months. In Acts 21, Paul is falsely accused of "teaching all the Jews who are among the Gentiles to forsake Moses, telling them not to circumcise their children nor to walk according to the customs." James and the elders in Jerusalem encouraged Paul to conclude his Nazarite vows with four other men in order to prove these charges were false and show that Paul "walked orderly, keeping the Law" (Acts 21:24).
Locusts upon the earth
Revelation 9 describes the trumpet of the fifth angel. When the fifth trumpet is sounded the bottomless pit is opened up and locusts come upon the earth. These locusts are given special power and are described in this manner:
The appearance of the locusts was like horses prepared for battle; and on their heads appeared to be crowns like gold, and their faces were like the faces of men. They had hair like the hair of women, and their teeth were like the teeth of lions. They had breastplates like breastplates of iron; and the sound of their wings was like the sound of chariots, of many horses rushing to battle. They have tails like scorpions, and stings; and in their tails is their power to hurt men for five months. They have as king over them, the angel of the abyss; his name in Hebrew is Abaddon, and in the Greek he has the name Apollyon.
This description is an expansion of the description given in Joel 1:4-6, 2:4-5. One of the additions is the "hair like hair of women". This might be a picture of those who would seek to overthrow the Kingdom. Consider David's son Absalom and his wealth of hair (2 Sam 14:25-26) and his attempt at taking over the kingdom (2 Sam 18:9-15) and how his hair became a snare as it was caught in a tree. His hair represents beauty and arrogance... both traits of Satan (Eze 28:15). It may be that these minions from the bottomless pit are described in such a manner.
From now until forever may honor and glory be to the Lord our G-d.