What 𝓽 means
Use Unicode hex input or a character picker.
In an app with hexadecimal Unicode entry, type 1D4FD and run its conversion command. A character picker can also find this cursive-looking t by its Unicode name; the exact keystroke varies by app.
What does 𝓽 mean in math?
It is a Latin lowercase t in bold mathematical script.
In a formula, that style can distinguish one symbol from plain t; it does not give the letter a universal value, so the surrounding notation tells you what it stands for.
By 2000, MathML, a web format for equations, already listed script letters among named mathematical alphabets. The encoded styles preserve distinctions that math typesetting already used, even when a formula is carried as plain text.
Don't confuse it with
1Questions people ask
2Why did 𝓽 turn into plain t?
Yes, that can happen. Unicode's NFKC compatibility normalization maps 𝓽 to plain Latin `t`, removing the mathematical style distinction.
Why does 𝓽 look different in different fonts?
The font determines the outline. One math font may draw it in roundhand, a rounded formal handwriting style; another may use chancery, a more slanted calligraphic style.
How to type 𝓽
𝓽\1D4FDCodes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.