I had better start rolling the ball...
In English the adjective little is often used to describe any small object or person, which means that little can act like a diminutive. For example, in English we'd say:
- a little old man (whereas in Italian un vecchio becomes un vecchietto)
- a little man (un uomo → un ometto)
- a little boy (ragazzo → ragazzino),
- a little lady / woman (donna → donnetta)
- a little baby/child/toddler (bambino → bimbetto)
- a little hand (or) a child's hand (mano → manina)
- a little car (macchina → macchinetta)
According to Diminutives in English, the terms “lady”, “woman”, “man” and “wife” normally refer to adult persons but when little is placed in front, the speaker may be reducing their social status to that of children, implying that their level of intelligence or importance is similar to that of children; as a result the speaker appears superior. If, however, forms such as “little man” or “little lady” are used for small boys or girls, these expressions tend to be complimentary.
In contrast, Italian commonly employs the suffixes -etto/a and ino/a, and very effectively too, I may add. If the OP were to use the suffix -let in any of the above expressions e.g., womanlet, or boylet, native speakers would think it very odd-sounding. They may not even recognize the OP's intended meaning.
Carlet as a diminutive for car, could work, but I imagine many would dismiss it as sounding rather twee and affected. Someone else might look it up in a dictionary, Merriam &Webster for instance, and discover it means a 3-square single-cut file used by combmakers. Frankly, I believe the need to use a diminutive suffix never arose.
In Diminutives in English (2003) by Klaus P. Schneider; Geoffrey Turner argues that the term little makes up for the lack of diminutives in the English language.
But perhaps in Old English there were suffixes that were used to this end. I don't know, unless I do some research...
... Yes, in Old English there were suffixes that were commonly used to change nouns into diminutive nouns, similar to the French -et, -ette, and the Italian -etto, and -ino. Many of the following terms have become rare or archaic, but some still survive today
Old and Middle English suffixes
-en Used to form the diminutives of certain nouns From Middle English, from Old English -en, from the neuter form of -en
- chicken (diminutive of coc, cocc)
- maiden (a girl or an unmarried young woman)
- kitten (a young cat)
-kin (now archaic) Forming diminutives of nouns. Middle English -kin, -kinne, -kunne, from Old English cynna
- boykin (a rare word meaning ‘a little boy’)
- catkin (a little cat)
- ladykin (a little lady)
- manikin (a short person)
-le A suffix forming diminutives from other nouns; compare -ling From Middle English -el, from Old English -el, -il (diminutive suffix)
- dimple (a small depression or indentation in a surface.)
- dingle (a small, narrow or enclosed, usually wooded valley.)
- hovel (a poor cottage; a small, mean house; a hut.)
- nipple (believed to be a diminutive of nib, neb (“tip, point”) nib + -le)
- nozzle (short tube, usually tapering, forming the vent of a hose or pipe.)
-ling A diminutive modifier of nouns having either the physical sense of "a younger, smaller or inferior version of what is denoted by the original noun" From Middle English -ling, from Old English -ling, from Proto-Germanic * -lingaz
- darling (dear+ling; someone who is dear to me)
- daughterling (a young or precious daughter)
- sonling (a young or precious son)
- fingerling (‘fingerling potato’=small potato)
- pigling ( a little or young pig, a piglet)
-ock nouns from nouns, originally with a diminutive sense. From Middle English -ock, from Old English -oc, -uc (diminutive suffix),
- bittock (a little bit; a small piece) Example: Then I cut the flesh into bittocks...
- bullock (an archaic term meaning a ‘young bull’)
- hattock (hat + -ock; a Scottish archaic word for a ‘small hat’)
- hillock (a small hill)
- maddock (an obsolete word meaning an earthworm, or a maggot)
- paddock (diminutive of pad, an archaic word for toad) Example: Paddock calls (Macbeth 1.1.10)
- whinnock (the smallest pig in a litter, a runt)
- Why can't a suffix like -let be applied to everyday terms like hand or
car? For example, handlet, or carlet.
The term car is derived from Middle English carre meaning a vehicle with wheels or a ‘[small] cart’. Its diminutive form, which was carete or carette, didn't make it to the 20th century and has become obsolete.
I didn't find a term that meant a ‘small hand’ or a ‘young hand’, although English does have the following terms which contain the suffixes -ling and -le: handling and handle, but their meanings are related to the activity that hands do; how something performs, is treated, manipulated or to the object that involves the use of hands.
We'll just have to make do with “little hand”.